diff --git a/lib/delphi/DelphiThrift.groupproj b/lib/delphi/DelphiThrift.groupproj
index 179f680..3a256dd 100644
--- a/lib/delphi/DelphiThrift.groupproj
+++ b/lib/delphi/DelphiThrift.groupproj
@@ -48,6 +48,9 @@
 			<Projects Include="test\skip\skiptest_version2.dproj">
 				<Dependencies/>
 			</Projects>
+			<Projects Include="test\serializer\SerializerData.dproj">
+				<Dependencies/>
+			</Projects>
 			<Projects Include="test\serializer\TestSerializer.dproj">
 				<Dependencies/>
 			</Projects>
@@ -143,6 +146,15 @@
 		<Target Name="skiptest_version2:Make">
 			<MSBuild Projects="test\skip\skiptest_version2.dproj" Targets="Make"/>
 		</Target>
+		<Target Name="SerializerData">
+			<MSBuild Projects="test\serializer\SerializerData.dproj"/>
+		</Target>
+		<Target Name="SerializerData:Clean">
+			<MSBuild Projects="test\serializer\SerializerData.dproj" Targets="Clean"/>
+		</Target>
+		<Target Name="SerializerData:Make">
+			<MSBuild Projects="test\serializer\SerializerData.dproj" Targets="Make"/>
+		</Target>
 		<Target Name="TestSerializer">
 			<MSBuild Projects="test\serializer\TestSerializer.dproj"/>
 		</Target>
@@ -162,13 +174,13 @@
 			<MSBuild Projects="test\typeregistry\TestTypeRegistry.dproj" Targets="Make"/>
 		</Target>
 		<Target Name="Build">
-			<CallTarget Targets="DelphiServer;DelphiClient;ReservedKeywords;client;server;Multiplex_Test_Client;Multiplex_Test_Server;skiptest_version1;skiptest_version2;TestSerializer;TestTypeRegistry"/>
+			<CallTarget Targets="DelphiServer;DelphiClient;ReservedKeywords;client;server;Multiplex_Test_Client;Multiplex_Test_Server;skiptest_version1;skiptest_version2;SerializerData;TestSerializer;TestTypeRegistry"/>
 		</Target>
 		<Target Name="Clean">
-			<CallTarget Targets="DelphiServer:Clean;DelphiClient:Clean;ReservedKeywords:Clean;client:Clean;server:Clean;Multiplex_Test_Client:Clean;Multiplex_Test_Server:Clean;skiptest_version1:Clean;skiptest_version2:Clean;TestSerializer:Clean;TestTypeRegistry:Clean"/>
+			<CallTarget Targets="DelphiServer:Clean;DelphiClient:Clean;ReservedKeywords:Clean;client:Clean;server:Clean;Multiplex_Test_Client:Clean;Multiplex_Test_Server:Clean;skiptest_version1:Clean;skiptest_version2:Clean;SerializerData:Clean;TestSerializer:Clean;TestTypeRegistry:Clean"/>
 		</Target>
 		<Target Name="Make">
-			<CallTarget Targets="DelphiServer:Make;DelphiClient:Make;ReservedKeywords:Make;client:Make;server:Make;Multiplex_Test_Client:Make;Multiplex_Test_Server:Make;skiptest_version1:Make;skiptest_version2:Make;TestSerializer:Make;TestTypeRegistry:Make"/>
+			<CallTarget Targets="DelphiServer:Make;DelphiClient:Make;ReservedKeywords:Make;client:Make;server:Make;Multiplex_Test_Client:Make;Multiplex_Test_Server:Make;skiptest_version1:Make;skiptest_version2:Make;SerializerData:Make;TestSerializer:Make;TestTypeRegistry:Make"/>
 		</Target>
 		<Import Condition="Exists('$(BDS)\Bin\CodeGear.Group.Targets')" Project="$(BDS)\Bin\CodeGear.Group.Targets"/>
 	</Project>
diff --git a/lib/delphi/src/Thrift.Protocol.pas b/lib/delphi/src/Thrift.Protocol.pas
index 03cc371..9f2cac8 100644
--- a/lib/delphi/src/Thrift.Protocol.pas
+++ b/lib/delphi/src/Thrift.Protocol.pas
@@ -193,8 +193,10 @@
     destructor Destroy; override;
   end;
 
+  IThriftBytes = interface; // forward
+
   IProtocol = interface
-    ['{F0040D99-937F-400D-9932-AF04F665899F}']
+    ['{6067A28E-15BF-4C9D-9A6F-D991BB3DCB85}']
     function GetTransport: ITransport;
     procedure WriteMessageBegin( const msg: TThriftMessage);
     procedure WriteMessageEnd;
@@ -217,7 +219,8 @@
     procedure WriteDouble( const d: Double);
     procedure WriteString( const s: string );
     procedure WriteAnsiString( const s: AnsiString);
-    procedure WriteBinary( const b: TBytes);
+    procedure WriteBinary( const b: TBytes); overload;
+    procedure WriteBinary( const b: IThriftBytes); overload;
 
     function ReadMessageBegin: TThriftMessage;
     procedure ReadMessageEnd();
@@ -237,7 +240,8 @@
     function ReadI32: Integer;
     function ReadI64: Int64;
     function ReadDouble:Double;
-    function ReadBinary: TBytes;
+    function ReadBinary: TBytes;  // IMPORTANT: this is NOT safe across module boundaries
+    function ReadBinaryCOM : IThriftBytes;
     function ReadString: string;
     function ReadAnsiString: AnsiString;
 
@@ -292,7 +296,7 @@
     procedure WriteDouble( const d: Double); virtual; abstract;
     procedure WriteString( const s: string ); virtual;
     procedure WriteAnsiString( const s: AnsiString); virtual;
-    procedure WriteBinary( const b: TBytes); virtual; abstract;
+    procedure WriteBinary( const b: TBytes); overload; virtual; abstract;
 
     function ReadMessageBegin: TThriftMessage; virtual; abstract;
     procedure ReadMessageEnd(); virtual; abstract;
@@ -316,6 +320,10 @@
     function ReadString: string; virtual;
     function ReadAnsiString: AnsiString; virtual;
 
+    // provide generic implementation for all derived classes
+    procedure WriteBinary( const bytes : IThriftBytes); overload; virtual;
+    function ReadBinaryCOM : IThriftBytes;  virtual;
+
     property  Transport: ITransport read GetTransport;
 
   public
@@ -324,8 +332,38 @@
 
   IBase = interface( ISupportsToString)
     ['{AFF6CECA-5200-4540-950E-9B89E0C1C00C}']
-    procedure Read( const iprot: IProtocol);
-    procedure Write( const iprot: IProtocol);
+    procedure Read( const prot: IProtocol);
+    procedure Write( const prot: IProtocol);
+  end;
+
+
+  IThriftBytes = interface( ISupportsToString)
+    ['{CDBEF7E8-BEF2-4A0A-983A-F334E3FF0016}']
+    function  GetCount : Integer;
+    procedure SetCount(const value : Integer);
+
+    // WARNING: This returns a direct pointer to the underlying data structure
+    function  QueryRawDataPtr : Pointer;
+
+    property Count : Integer read GetCount write SetCount;
+  end;
+
+
+  TThriftBytesImpl = class( TInterfacedObject, IThriftBytes, ISupportsToString)
+  strict private
+    FData : TBytes;
+
+  strict protected
+    function  GetCount : Integer;
+    procedure SetCount(const value : Integer);
+    function  QueryRawDataPtr : Pointer;
+
+  public
+    constructor Create; overload;
+    constructor Create( const bytes : TBytes); overload;
+    constructor Create( var bytes : TBytes; const aTakeOwnership : Boolean = FALSE); overload;
+
+    function ToString : string; override;
   end;
 
 
@@ -653,6 +691,95 @@
   FTrans.CheckReadBytesAvailable( value.Count * nPairSize);
 end;
 
+
+procedure TProtocolImpl.WriteBinary( const bytes : IThriftBytes);
+var tmp : TBytes;
+begin
+  SetLength( tmp, bytes.Count);
+  if Length(tmp) > 0
+  then Move( bytes.QueryRawDataPtr^, tmp[0], Length(tmp));
+  WriteBinary( tmp);
+end;
+
+
+function TProtocolImpl.ReadBinaryCOM : IThriftBytes;
+var bytes : TBytes;
+begin
+  bytes := ReadBinary;
+  result := TThriftBytesImpl.Create(bytes,TRUE);
+end;
+
+
+{ TThriftBytesImpl }
+
+constructor TThriftBytesImpl.Create;
+begin
+  inherited Create;
+  ASSERT( Length(FData) = 0);
+end;
+
+
+constructor TThriftBytesImpl.Create( const bytes : TBytes);
+begin
+  FData := bytes; // copies the data
+end;
+
+
+constructor TThriftBytesImpl.Create( var bytes : TBytes; const aTakeOwnership : Boolean);
+
+  procedure SwapPointer( var one, two);
+  var
+    pOne : Pointer absolute one;
+    pTwo : Pointer absolute two;
+    pTmp : Pointer;
+  begin
+    pTmp := pOne;
+    pOne := pTwo;
+    pTwo := pTmp;
+  end;
+
+begin
+  inherited Create;
+  ASSERT( Length(FData) = 0);
+
+  if aTakeOwnership
+  then SwapPointer( FData, bytes)
+  else FData := bytes; // copies the data
+end;
+
+
+function TThriftBytesImpl.ToString : string;
+var sb : TThriftStringBuilder;
+begin
+  sb := TThriftStringBuilder.Create();
+  try
+    sb.Append('Bin: ');
+    sb.Append( FData);
+
+    result := sb.ToString;
+  finally
+    sb.Free;
+  end;
+end;
+
+
+function TThriftBytesImpl.GetCount : Integer;
+begin
+  result := Length(FData);
+end;
+
+
+procedure TThriftBytesImpl.SetCount(const value : Integer);
+begin
+  SetLength( FData, value);
+end;
+
+
+function TThriftBytesImpl.QueryRawDataPtr : Pointer;
+begin
+  result := FData;
+end;
+
 { TProtocolUtil }
 
 class procedure TProtocolUtil.Skip( prot: IProtocol; type_: TType);
diff --git a/lib/delphi/test/serializer/SerializerData.dpr b/lib/delphi/test/serializer/SerializerData.dpr
new file mode 100644
index 0000000..92ed00b
--- /dev/null
+++ b/lib/delphi/test/serializer/SerializerData.dpr
@@ -0,0 +1,82 @@
+library SerializerData;
+(*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *)
+
+uses
+  Classes,
+  Windows,
+  SysUtils,
+  Generics.Collections,
+  Thrift in '..\..\src\Thrift.pas',
+  Thrift.Exception in '..\..\src\Thrift.Exception.pas',
+  Thrift.Socket in '..\..\src\Thrift.Socket.pas',
+  Thrift.Transport in '..\..\src\Thrift.Transport.pas',
+  Thrift.Protocol in '..\..\src\Thrift.Protocol.pas',
+  Thrift.Protocol.JSON in '..\..\src\Thrift.Protocol.JSON.pas',
+  Thrift.Protocol.Compact in '..\..\src\Thrift.Protocol.Compact.pas',
+  Thrift.Collections in '..\..\src\Thrift.Collections.pas',
+  Thrift.Configuration in '..\..\src\Thrift.Configuration.pas',
+  Thrift.Server in '..\..\src\Thrift.Server.pas',
+  Thrift.Utils in '..\..\src\Thrift.Utils.pas',
+  Thrift.Serializer in '..\..\src\Thrift.Serializer.pas',
+  Thrift.Stream in '..\..\src\Thrift.Stream.pas',
+  Thrift.WinHTTP in '..\..\src\Thrift.WinHTTP.pas',
+  Thrift.TypeRegistry in '..\..\src\Thrift.TypeRegistry.pas',
+  System_ in 'gen-delphi\System_.pas',
+  SysUtils_ in 'gen-delphi\SysUtils_.pas',
+  DebugProtoTest in 'gen-delphi\DebugProtoTest.pas',
+  TestSerializer.Data in 'TestSerializer.Data.pas';
+
+{$R *.res}
+
+function CreateOneOfEach : IOneOfEach; stdcall;
+begin
+  result := Fixtures.CreateOneOfEach;
+end;
+
+
+function CreateNesting : INesting; stdcall;
+begin
+  result := Fixtures.CreateNesting;
+end;
+
+
+function CreateHolyMoley : IHolyMoley; stdcall;
+begin
+  result := Fixtures.CreateHolyMoley;
+end;
+
+
+function CreateCompactProtoTestStruct : ICompactProtoTestStruct; stdcall;
+begin
+  result := Fixtures.CreateCompactProtoTestStruct;
+end;
+
+
+exports
+  CreateOneOfEach,
+  CreateNesting,
+  CreateHolyMoley,
+  CreateCompactProtoTestStruct;
+
+begin
+  IsMultiThread := TRUE;
+  ASSERT( cDebugProtoTest_Option_COM_types);
+  ASSERT( cSystem__Option_COM_types);
+end.
diff --git a/lib/delphi/test/serializer/SerializerData.dproj b/lib/delphi/test/serializer/SerializerData.dproj
new file mode 100644
index 0000000..cfc27f8
--- /dev/null
+++ b/lib/delphi/test/serializer/SerializerData.dproj
@@ -0,0 +1,150 @@
+﻿<!--
+ Licensed to the Apache Software Foundation (ASF) under one
+ or more contributor license agreements. See the NOTICE file
+ distributed with this work for additional information
+ regarding copyright ownership. The ASF licenses this file
+ to you under the Apache License, Version 2.0 (the
+ "License"); you may not use this file except in compliance
+ with the License. You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing,
+ software distributed under the License is distributed on an
+ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ KIND, either express or implied. See the License for the
+ specific language governing permissions and limitations
+ under the License.
+-->
+	<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+		<PropertyGroup>
+			<ProjectGuid>{B523D1D7-2C9A-4B39-A6CF-69EF536D5079}</ProjectGuid>
+			<MainSource>SerializerData.dpr</MainSource>
+			<ProjectVersion>12.3</ProjectVersion>
+			<Basis>True</Basis>
+			<Config Condition="'$(Config)'==''">Debug</Config>
+			<Platform>Win32</Platform>
+			<AppType>Library</AppType>
+			<FrameworkType>None</FrameworkType>
+			<DCC_DCCCompiler>DCC32</DCC_DCCCompiler>
+		</PropertyGroup>
+		<PropertyGroup Condition="'$(Config)'=='Basis' or '$(Base)'!=''">
+			<Base>true</Base>
+		</PropertyGroup>
+		<PropertyGroup Condition="'$(Config)'=='Debug' or '$(Cfg_1)'!=''">
+			<Cfg_1>true</Cfg_1>
+			<CfgParent>Base</CfgParent>
+			<Base>true</Base>
+		</PropertyGroup>
+		<PropertyGroup Condition="'$(Config)'=='Release' or '$(Cfg_2)'!=''">
+			<Cfg_2>true</Cfg_2>
+			<CfgParent>Base</CfgParent>
+			<Base>true</Base>
+		</PropertyGroup>
+		<PropertyGroup Condition="'$(Base)'!=''">
+			<DCC_DcuOutput>.\$(Config)\$(Platform)</DCC_DcuOutput>
+			<DCC_E>false</DCC_E>
+			<DCC_ImageBase>00400000</DCC_ImageBase>
+			<DCC_UnitAlias>WinTypes=Windows;WinProcs=Windows;DbiTypes=BDE;DbiProcs=BDE;$(DCC_UnitAlias)</DCC_UnitAlias>
+			<DCC_ExeOutput>bin\$(Config)\$(Platform)</DCC_ExeOutput>
+			<DCC_S>false</DCC_S>
+			<GenDll>true</GenDll>
+			<DCC_N>false</DCC_N>
+			<DCC_F>false</DCC_F>
+			<DCC_K>false</DCC_K>
+		</PropertyGroup>
+		<PropertyGroup Condition="'$(Cfg_1)'!=''">
+			<DCC_Define>DEBUG;$(DCC_Define)</DCC_Define>
+			<DCC_Optimize>false</DCC_Optimize>
+			<DCC_GenerateStackFrames>true</DCC_GenerateStackFrames>
+		</PropertyGroup>
+		<PropertyGroup Condition="'$(Cfg_2)'!=''">
+			<DCC_LocalDebugSymbols>false</DCC_LocalDebugSymbols>
+			<DCC_Define>RELEASE;$(DCC_Define)</DCC_Define>
+			<DCC_SymbolReferenceInfo>0</DCC_SymbolReferenceInfo>
+			<DCC_DebugInformation>false</DCC_DebugInformation>
+		</PropertyGroup>
+		<ItemGroup>
+			<DelphiCompile Include="SerializerData.dpr">
+				<MainSource>MainSource</MainSource>
+			</DelphiCompile>
+			<DCCReference Include="..\..\src\Thrift.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Exception.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Socket.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Transport.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Protocol.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Protocol.JSON.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Protocol.Compact.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Collections.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Configuration.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Server.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Utils.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Serializer.pas"/>
+			<DCCReference Include="..\..\src\Thrift.Stream.pas"/>
+			<DCCReference Include="..\..\src\Thrift.WinHTTP.pas"/>
+			<DCCReference Include="..\..\src\Thrift.TypeRegistry.pas"/>
+			<DCCReference Include="gen-delphi\System_.pas"/>
+			<DCCReference Include="gen-delphi\SysUtils_.pas"/>
+			<DCCReference Include="gen-delphi\DebugProtoTest.pas"/>
+			<DCCReference Include="TestSerializer.Data.pas"/>
+			<BuildConfiguration Include="Release">
+				<Key>Cfg_2</Key>
+				<CfgParent>Base</CfgParent>
+			</BuildConfiguration>
+			<BuildConfiguration Include="Basis">
+				<Key>Base</Key>
+			</BuildConfiguration>
+			<BuildConfiguration Include="Debug">
+				<Key>Cfg_1</Key>
+				<CfgParent>Base</CfgParent>
+			</BuildConfiguration>
+		</ItemGroup>
+		<Import Condition="Exists('$(BDS)\Bin\CodeGear.Delphi.Targets')" Project="$(BDS)\Bin\CodeGear.Delphi.Targets"/>
+		<Import Condition="Exists('$(APPDATA)\Embarcadero\$(BDSAPPDATABASEDIR)\$(PRODUCTVERSION)\UserTools.proj')" Project="$(APPDATA)\Embarcadero\$(BDSAPPDATABASEDIR)\$(PRODUCTVERSION)\UserTools.proj"/>
+		<PropertyGroup>
+			<PreBuildEvent><![CDATA[thrift.exe -r -gen delphi:com_types ..\keywords\ReservedKeywords.thrift
+thrift.exe -r -gen delphi:com_types ..\..\..\..\test\DebugProtoTest.thrift]]></PreBuildEvent>
+		</PropertyGroup>
+		<ProjectExtensions>
+			<Borland.Personality>Delphi.Personality.12</Borland.Personality>
+			<Borland.ProjectType/>
+			<BorlandProject>
+				<Delphi.Personality>
+					<VersionInfo>
+						<VersionInfo Name="IncludeVerInfo">False</VersionInfo>
+						<VersionInfo Name="AutoIncBuild">False</VersionInfo>
+						<VersionInfo Name="MajorVer">1</VersionInfo>
+						<VersionInfo Name="MinorVer">0</VersionInfo>
+						<VersionInfo Name="Release">0</VersionInfo>
+						<VersionInfo Name="Build">0</VersionInfo>
+						<VersionInfo Name="Debug">False</VersionInfo>
+						<VersionInfo Name="PreRelease">False</VersionInfo>
+						<VersionInfo Name="Special">False</VersionInfo>
+						<VersionInfo Name="Private">False</VersionInfo>
+						<VersionInfo Name="DLL">False</VersionInfo>
+						<VersionInfo Name="Locale">1031</VersionInfo>
+						<VersionInfo Name="CodePage">1252</VersionInfo>
+					</VersionInfo>
+					<VersionInfoKeys>
+						<VersionInfoKeys Name="CompanyName"/>
+						<VersionInfoKeys Name="FileDescription"/>
+						<VersionInfoKeys Name="FileVersion">1.0.0.0</VersionInfoKeys>
+						<VersionInfoKeys Name="InternalName"/>
+						<VersionInfoKeys Name="LegalCopyright"/>
+						<VersionInfoKeys Name="LegalTrademarks"/>
+						<VersionInfoKeys Name="OriginalFilename"/>
+						<VersionInfoKeys Name="ProductName"/>
+						<VersionInfoKeys Name="ProductVersion">1.0.0.0</VersionInfoKeys>
+						<VersionInfoKeys Name="Comments"/>
+					</VersionInfoKeys>
+					<Source>
+						<Source Name="MainSource">SerializerData.dpr</Source>
+					</Source>
+				</Delphi.Personality>
+				<Platforms>
+					<Platform value="Win32">True</Platform>
+				</Platforms>
+			</BorlandProject>
+			<ProjectFileVersion>12</ProjectFileVersion>
+		</ProjectExtensions>
+	</Project>
diff --git a/lib/delphi/test/serializer/SerializerData.res b/lib/delphi/test/serializer/SerializerData.res
new file mode 100644
index 0000000..231eb70
--- /dev/null
+++ b/lib/delphi/test/serializer/SerializerData.res
Binary files differ
diff --git a/lib/delphi/test/serializer/TestSerializer.Data.pas b/lib/delphi/test/serializer/TestSerializer.Data.pas
index af366fd..4b8cc66 100644
--- a/lib/delphi/test/serializer/TestSerializer.Data.pas
+++ b/lib/delphi/test/serializer/TestSerializer.Data.pas
@@ -23,6 +23,7 @@
 
 uses
   SysUtils,
+  Thrift.Protocol,
   Thrift.Collections,
   DebugProtoTest;
 
@@ -194,6 +195,8 @@
 
   {$IF cDebugProtoTest_Option_AnsiStr_Binary}
   result.SetBase64('base64');
+  {$ELSEIF cDebugProtoTest_Option_COM_Types}
+  result.SetBase64( TThriftBytesImpl.Create( TEncoding.UTF8.GetBytes('base64')));
   {$ELSE}
   result.SetBase64( TEncoding.UTF8.GetBytes('base64'));
   {$IFEND}
@@ -216,8 +219,10 @@
 
 
 class function Fixtures.CreateHolyMoley : IHolyMoley;
+type
+  TStringType = {$IF cDebugProtoTest_Option_COM_Types} WideString {$ELSE} String {$IFEND};
 var big : IThriftList<IOneOfEach>;
-    stage1 : IThriftList<String>;
+    stage1 : IThriftList<TStringType>;
     stage2 : IThriftList<IBonk>;
     b      : IBonk;
 begin
@@ -230,23 +235,23 @@
   result.Big[0].setA_bite( $22);
   result.Big[0].setA_bite( $23);
 
-  result.Contain := TThriftHashSetImpl< IThriftList<string>>.Create;
-  stage1 := TThriftListImpl<String>.Create;
+  result.Contain := TThriftHashSetImpl< IThriftList<TStringType>>.Create;
+  stage1 := TThriftListImpl<TStringType>.Create;
   stage1.add( 'and a one');
   stage1.add( 'and a two');
   result.Contain.add( stage1);
 
-  stage1 := TThriftListImpl<String>.Create;
+  stage1 := TThriftListImpl<TStringType>.Create;
   stage1.add( 'then a one, two');
   stage1.add( 'three!');
   stage1.add( 'FOUR!!');
   result.Contain.add( stage1);
 
-  stage1 := TThriftListImpl<String>.Create;
+  stage1 := TThriftListImpl<TStringType>.Create;
   result.Contain.add( stage1);
 
   stage2 := TThriftListImpl<IBonk>.Create;
-  result.Bonks := TThriftDictionaryImpl< String, IThriftList< IBonk>>.Create;
+  result.Bonks := TThriftDictionaryImpl< TStringType, IThriftList< IBonk>>.Create;
   // one empty
   result.Bonks.Add( 'zero', stage2);
 
@@ -342,6 +347,8 @@
 
   {$IF cDebugProtoTest_Option_AnsiStr_Binary}
   result.A_binary := AnsiString( #0#1#2#3#4#5#6#7#8);
+  {$ELSEIF cDebugProtoTest_Option_COM_Types}
+  result.A_binary := TThriftBytesImpl.Create( TEncoding.UTF8.GetBytes( #0#1#2#3#4#5#6#7#8));
   {$ELSE}
   result.A_binary := TEncoding.UTF8.GetBytes( #0#1#2#3#4#5#6#7#8);
   {$IFEND}
diff --git a/lib/delphi/test/serializer/TestSerializer.Tests.pas b/lib/delphi/test/serializer/TestSerializer.Tests.pas
index 83d67b1..443a22d 100644
--- a/lib/delphi/test/serializer/TestSerializer.Tests.pas
+++ b/lib/delphi/test/serializer/TestSerializer.Tests.pas
@@ -41,8 +41,7 @@
   Thrift.WinHTTP,
   Thrift.TypeRegistry,
   System_,
-  DebugProtoTest,
-  TestSerializer.Data;
+  DebugProtoTest;
 
 
 type
@@ -58,7 +57,7 @@
       mt_Stream
     );
 
-  private
+  strict private
     FProtocols : TList< TFactoryPair>;
     procedure AddFactoryCombination( const aProto : IProtocolFactory; const aTrans : ITransportFactory);
     class function UserFriendlyName( const factory : TFactoryPair) : string;  overload;
@@ -73,7 +72,14 @@
     class procedure ValidateReadToEnd( const input : TBytes; const serial : TDeserializer);  overload;
     class procedure ValidateReadToEnd( const input : TStream; const serial : TDeserializer);  overload;
 
+    class function LengthOf( const bytes : TBytes) : Integer; overload; inline;
+    class function LengthOf( const bytes : IThriftBytes) : Integer; overload; inline;
+
+    class function DataPtrOf( const bytes : TBytes) : Pointer; overload; inline;
+    class function DataPtrOf( const bytes : IThriftBytes) : Pointer; overload; inline;
+
     procedure Test_Serializer_Deserializer;
+    procedure Test_COM_Types;
     procedure Test_OneOfEach(     const method : TMethod; const factory : TFactoryPair; const stream : TFileStream);
     procedure Test_CompactStruct( const method : TMethod; const factory : TFactoryPair; const stream : TFileStream);
 
@@ -87,6 +93,12 @@
 
 implementation
 
+const SERIALIZERDATA_DLL = 'SerializerData.dll';
+function CreateOneOfEach : IOneOfEach; stdcall; external SERIALIZERDATA_DLL;
+function CreateNesting : INesting; stdcall; external SERIALIZERDATA_DLL;
+function CreateHolyMoley : IHolyMoley; stdcall; external SERIALIZERDATA_DLL;
+function CreateCompactProtoTestStruct : ICompactProtoTestStruct; stdcall; external SERIALIZERDATA_DLL;
+
 
 { TTestSerializer }
 
@@ -128,13 +140,41 @@
 end;
 
 
+class function TTestSerializer.LengthOf( const bytes : TBytes) : Integer;
+begin
+  result := Length(bytes);
+end;
+
+
+class function TTestSerializer.LengthOf( const bytes : IThriftBytes) : Integer;
+begin
+  if bytes <> nil
+  then result := bytes.Count
+  else result := 0;
+end;
+
+
+class function TTestSerializer.DataPtrOf( const bytes : TBytes) : Pointer;
+begin
+  result := bytes;
+end;
+
+
+class function TTestSerializer.DataPtrOf( const bytes : IThriftBytes) : Pointer;
+begin
+  if bytes <> nil
+  then result := bytes.QueryRawDataPtr
+  else result := nil;
+end;
+
+
 procedure TTestSerializer.Test_OneOfEach( const method : TMethod; const factory : TFactoryPair; const stream : TFileStream);
 var tested, correct : IOneOfEach;
     bytes   : TBytes;
     i : Integer;
 begin
   // write
-  tested := Fixtures.CreateOneOfEach;
+  tested := CreateOneOfEach;
   case method of
     mt_Bytes:  bytes := Serialize( tested, factory);
     mt_Stream: begin
@@ -158,7 +198,7 @@
   end;
 
   // check
-  correct := Fixtures.CreateOneOfEach;
+  correct := CreateOneOfEach;
   ASSERT( tested.Im_true = correct.Im_true);
   ASSERT( tested.Im_false = correct.Im_false);
   ASSERT( tested.A_bite = correct.A_bite);
@@ -170,8 +210,8 @@
   ASSERT( tested.Zomg_unicode = correct.Zomg_unicode);
   ASSERT( tested.What_who = correct.What_who);
 
-  ASSERT( Length(tested.Base64) = Length(correct.Base64));
-  ASSERT( CompareMem( @tested.Base64[0], @correct.Base64[0], Length(correct.Base64)));
+  ASSERT( LengthOf(tested.Base64) = LengthOf(correct.Base64));
+  ASSERT( CompareMem( DataPtrOf(tested.Base64), DataPtrOf(correct.Base64), LengthOf(correct.Base64)));
 
   ASSERT( tested.Byte_list.Count = correct.Byte_list.Count);
   for i := 0 to tested.Byte_list.Count-1
@@ -192,7 +232,7 @@
     bytes   : TBytes;
 begin
   // write
-  tested := Fixtures.CreateCompactProtoTestStruct;
+  tested := CreateCompactProtoTestStruct;
   case method of
     mt_Bytes:  bytes := Serialize( tested, factory);
     mt_Stream: begin
@@ -216,7 +256,7 @@
   end;
 
   // check
-  correct := Fixtures.CreateCompactProtoTestStruct;
+  correct := CreateCompactProtoTestStruct;
   ASSERT( correct.Field500  = tested.Field500);
   ASSERT( correct.Field5000  = tested.Field5000);
   ASSERT( correct.Field20000 = tested.Field20000);
@@ -269,10 +309,25 @@
 end;
 
 
+procedure TTestSerializer.Test_COM_Types;
+var tested : IOneOfEach;
+begin
+  {$IF cDebugProtoTest_Option_COM_types}
+  ASSERT( SizeOf(TSomeEnum) = SizeOf(Int32));  // -> MINENUMSIZE 4
+
+  // try to set values that allocate memory
+  tested := CreateOneOfEach;
+  tested.Zomg_unicode := 'This is a test';
+  tested.Base64 := TThriftBytesImpl.Create( TEncoding.UTF8.GetBytes('abc'));
+  {$IFEND}
+end;
+
+
 procedure TTestSerializer.RunTests;
 begin
   try
     Test_Serializer_Deserializer;
+    Test_COM_Types;
   except
     on e:Exception do begin
       Writeln( e.ClassName+': '+ e.Message);
diff --git a/lib/delphi/test/serializer/TestSerializer.dpr b/lib/delphi/test/serializer/TestSerializer.dpr
index 971401e..b78c0db 100644
--- a/lib/delphi/test/serializer/TestSerializer.dpr
+++ b/lib/delphi/test/serializer/TestSerializer.dpr
@@ -44,8 +44,7 @@
   System_ in 'gen-delphi\System_.pas',
   SysUtils_ in 'gen-delphi\SysUtils_.pas',
   DebugProtoTest in 'gen-delphi\DebugProtoTest.pas',
-  TestSerializer.Tests in 'TestSerializer.Tests.pas',
-  TestSerializer.Data in 'TestSerializer.Data.pas';
+  TestSerializer.Tests in 'TestSerializer.Tests.pas';
 
 
 var test : TTestSerializer;
diff --git a/lib/delphi/test/serializer/TestSerializer.dproj b/lib/delphi/test/serializer/TestSerializer.dproj
index 5f26264..1d98d3a 100644
--- a/lib/delphi/test/serializer/TestSerializer.dproj
+++ b/lib/delphi/test/serializer/TestSerializer.dproj
@@ -86,7 +86,6 @@
 			<DCCReference Include="gen-delphi\SysUtils_.pas"/>
 			<DCCReference Include="gen-delphi\DebugProtoTest.pas"/>
 			<DCCReference Include="TestSerializer.Tests.pas"/>
-			<DCCReference Include="TestSerializer.Data.pas"/>
 			<BuildConfiguration Include="Debug">
 				<Key>Cfg_2</Key>
 				<CfgParent>Base</CfgParent>
@@ -102,8 +101,8 @@
 		<Import Condition="Exists('$(BDS)\Bin\CodeGear.Delphi.Targets')" Project="$(BDS)\Bin\CodeGear.Delphi.Targets"/>
 		<Import Condition="Exists('$(APPDATA)\Embarcadero\$(BDSAPPDATABASEDIR)\$(PRODUCTVERSION)\UserTools.proj')" Project="$(APPDATA)\Embarcadero\$(BDSAPPDATABASEDIR)\$(PRODUCTVERSION)\UserTools.proj"/>
 		<PropertyGroup>
-			<PreBuildEvent><![CDATA[thrift.exe -r -gen delphi ..\keywords\ReservedKeywords.thrift
-thrift.exe -r -gen delphi ..\..\..\..\test\DebugProtoTest.thrift]]></PreBuildEvent>
+			<PreBuildEvent><![CDATA[thrift.exe -r -gen delphi:com_types ..\keywords\ReservedKeywords.thrift
+thrift.exe -r -gen delphi:com_types ..\..\..\..\test\DebugProtoTest.thrift]]></PreBuildEvent>
 		</PropertyGroup>
 		<ProjectExtensions>
 			<Borland.Personality>Delphi.Personality.12</Borland.Personality>