diff --git a/lib/delphi/test/TestServer.pas b/lib/delphi/test/TestServer.pas
index 3ae82a1..1e3a393 100644
--- a/lib/delphi/test/TestServer.pas
+++ b/lib/delphi/test/TestServer.pas
@@ -55,7 +55,7 @@
         procedure TestStop;
       end;
 
-      TTestHandlerImpl = class( TInterfacedObject, ITestHandler )
+      TTestHandlerImpl = class( TInterfacedObject, ITestHandler, TThriftTest.Iface)
       strict private
         FServer : IServer;
       strict protected