diff --git a/lib/cpp/src/protocol/TBinaryProtocol.cc b/lib/cpp/src/protocol/TBinaryProtocol.cc
index 3cd11ba..f2fbe87 100644
--- a/lib/cpp/src/protocol/TBinaryProtocol.cc
+++ b/lib/cpp/src/protocol/TBinaryProtocol.cc
@@ -48,11 +48,11 @@
 uint32_t TBinaryProtocol::writeMapBegin(shared_ptr<TTransport> out,
                                         const TType keyType,
                                         const TType valType,
-                                        const int32_t size) const {
+                                        const uint32_t size) const {
   return
     writeByte(out, (uint8_t)keyType) +
     writeByte(out, (uint8_t)valType) +
-    writeI32(out, (int32_t)size);
+    writeU32(out, (uint32_t)size);
 }
 
 uint32_t TBinaryProtocol::writeMapEnd(shared_ptr<TTransport> out) const {
@@ -61,10 +61,10 @@
 
 uint32_t TBinaryProtocol::writeListBegin(shared_ptr<TTransport> out,
                                          const TType elemType,
-                                         const int32_t size) const {
+                                         const uint32_t size) const {
   return
     writeByte(out, (uint8_t) elemType) +
-    writeI32(out, (int32_t)size);
+    writeU32(out, (int32_t)size);
 }
 
 uint32_t TBinaryProtocol::writeListEnd(shared_ptr<TTransport> out) const {
@@ -73,10 +73,10 @@
 
 uint32_t TBinaryProtocol::writeSetBegin(shared_ptr<TTransport> out,
                                         const TType elemType,
-                                        const int32_t size) const {
+                                        const uint32_t size) const {
   return
     writeByte(out, (uint8_t)elemType) +
-    writeI32(out, (int32_t)size);
+    writeU32(out, (int32_t)size);
 }
 
 uint32_t TBinaryProtocol::writeSetEnd(shared_ptr<TTransport> out) const {
@@ -200,14 +200,14 @@
 uint32_t TBinaryProtocol::readMapBegin(shared_ptr<TTransport> in,
                                        TType& keyType,
                                        TType& valType,
-                                       int32_t& size) const {
+                                       uint32_t& size) const {
   uint8_t k, v;
   uint32_t result = 0;
   result += readByte(in, k);
   keyType = (TType)k;
   result += readByte(in, v);
   valType = (TType)v;
-  result += readI32(in, size);
+  result += readU32(in, size);
   return result;
 }
 
@@ -217,12 +217,12 @@
 
 uint32_t TBinaryProtocol::readListBegin(shared_ptr<TTransport> in,
                                         TType& elemType,
-                                        int32_t& size) const {
+                                        uint32_t& size) const {
   uint8_t e;
   uint32_t result = 0;
   result += readByte(in, e);
   elemType = (TType)e;
-  result += readI32(in, size);
+  result += readU32(in, size);
   return result;
 }
 
@@ -232,12 +232,12 @@
 
 uint32_t TBinaryProtocol::readSetBegin(shared_ptr<TTransport> in,
                                        TType& elemType,
-                                       int32_t& size) const {
+                                       uint32_t& size) const {
   uint8_t e;
   uint32_t result = 0;
   result += readByte(in, e);
   elemType = (TType)e;
-  result += readI32(in, size);
+  result += readU32(in, size);
   return result;
 }
 
@@ -318,8 +318,8 @@
 uint32_t TBinaryProtocol::readString(shared_ptr<TTransport> in,
                                      string& str) const {
   uint32_t result;
-  int32_t size;
-  result = readI32(in, size);
+  uint32_t size;
+  result = readU32(in, size);
 
   // Use the heap here to prevent stack overflow for v. large strings
   uint8_t *b = new uint8_t[size];
diff --git a/lib/cpp/src/protocol/TBinaryProtocol.h b/lib/cpp/src/protocol/TBinaryProtocol.h
index 480182d..7780f16 100644
--- a/lib/cpp/src/protocol/TBinaryProtocol.h
+++ b/lib/cpp/src/protocol/TBinaryProtocol.h
@@ -49,19 +49,19 @@
   uint32_t writeMapBegin(shared_ptr<TTransport> out,
 			  const TType keyType,
 			  const TType valType,
-			  const int32_t size) const;
+			  const uint32_t size) const;
 
   uint32_t writeMapEnd(shared_ptr<TTransport> out) const;
 
   uint32_t writeListBegin(shared_ptr<TTransport> out,
 			   const TType elemType,
-			   const int32_t size) const;
+			   const uint32_t size) const;
 
   uint32_t writeListEnd(shared_ptr<TTransport> out) const;
 
   uint32_t writeSetBegin(shared_ptr<TTransport> out,
 			  const TType elemType,
-			  const int32_t size) const;
+			  const uint32_t size) const;
 
   uint32_t writeSetEnd(shared_ptr<TTransport> out) const;
 
@@ -119,19 +119,19 @@
   uint32_t readMapBegin(shared_ptr<TTransport> in,
 			 TType& keyType,
 			 TType& valType,
-			 int32_t& size) const;
+			 uint32_t& size) const;
 
   uint32_t readMapEnd(shared_ptr<TTransport> in) const;
 
   uint32_t readListBegin(shared_ptr<TTransport> in,
 			  TType& elemType,
-			  int32_t& size) const;
+			  uint32_t& size) const;
   
   uint32_t readListEnd(shared_ptr<TTransport> in) const;
 
   uint32_t readSetBegin(shared_ptr<TTransport> in,
 			 TType& elemType,
-			 int32_t& size) const;
+			 uint32_t& size) const;
 
   uint32_t readSetEnd(shared_ptr<TTransport> in) const;
 
diff --git a/lib/cpp/src/protocol/TProtocol.h b/lib/cpp/src/protocol/TProtocol.h
index 7dbb4a0..38c5347 100644
--- a/lib/cpp/src/protocol/TProtocol.h
+++ b/lib/cpp/src/protocol/TProtocol.h
@@ -103,19 +103,19 @@
   virtual uint32_t writeMapBegin(shared_ptr<TTransport> out,
 				 const TType keyType,
 				 const TType valType,
-				 const int32_t size) const = 0;
+				 const uint32_t size) const = 0;
 
   virtual uint32_t writeMapEnd(shared_ptr<TTransport> out) const = 0;
   
   virtual uint32_t writeListBegin(shared_ptr<TTransport> out,
 				  const TType elemType,
-				  const int32_t size) const = 0;
+				  const uint32_t size) const = 0;
 
   virtual uint32_t writeListEnd(shared_ptr<TTransport> out) const = 0;
 
   virtual uint32_t writeSetBegin(shared_ptr<TTransport> out,
 				 const TType elemType,
-				 const int32_t size) const = 0;
+				 const uint32_t size) const = 0;
 
   virtual uint32_t writeSetEnd(shared_ptr<TTransport> out) const = 0;
 
@@ -172,19 +172,19 @@
   virtual uint32_t readMapBegin(shared_ptr<TTransport> in,
 				TType& keyType,
 				TType& valType,
-				int32_t& size) const = 0;
+				uint32_t& size) const = 0;
 
   virtual uint32_t readMapEnd(shared_ptr<TTransport> in) const = 0;
 
   virtual uint32_t readListBegin(shared_ptr<TTransport> in,
 				 TType& elemType,
-				 int32_t& size) const = 0;
+				 uint32_t& size) const = 0;
 
   virtual uint32_t readListEnd(shared_ptr<TTransport> in) const = 0;
 
   virtual uint32_t readSetBegin(shared_ptr<TTransport> in,
 				TType& elemType,
-				int32_t& size) const = 0;
+				uint32_t& size) const = 0;
 
   virtual uint32_t readSetEnd(shared_ptr<TTransport> in) const = 0;
 
@@ -273,7 +273,7 @@
         uint32_t result = 0;
         TType keyType;
         TType valType;
-        int32_t i, size;
+        uint32_t i, size;
         result += readMapBegin(in, keyType, valType, size);
         for (i = 0; i < size; i++) {
           result += skip(in, keyType);
@@ -286,7 +286,7 @@
       {
         uint32_t result = 0;
         TType elemType;
-        int32_t i, size;
+        uint32_t i, size;
         result += readSetBegin(in, elemType, size);
         for (i = 0; i < size; i++) {
           result += skip(in, elemType);
@@ -298,7 +298,7 @@
       {
         uint32_t result = 0;
         TType elemType;
-        int32_t i, size;
+        uint32_t i, size;
         result += readListBegin(in, elemType, size);
         for (i = 0; i < size; i++) {
           result += skip(in, elemType);