diff --git a/gstreamer-sharp/Makefile.am b/gstreamer-sharp/Makefile.am
index b4e7dbb96e..b0e1dc6fe7 100644
--- a/gstreamer-sharp/Makefile.am
+++ b/gstreamer-sharp/Makefile.am
@@ -158,7 +158,7 @@ $(KEYFILE): $(top_srcdir)/gstreamer-sharp.snk
 	cp $(top_srcdir)/gstreamer-sharp.snk .
 
 $(ASSEMBLY): $(build_sources) generated-stamp $(KEYFILE) $(plugin_csfiles)
-	$(CSC) -nowarn:0612 -debug -unsafe -out:$(ASSEMBLY) -target:library $(references) $(csc_build_sources) $(GENERATED_SOURCES) $(plugin_csfiles) -define:GTK_SHARP_2_6 -define:GTK_SHARP_2_8 -define:GTK_SHARP_2_10 -define:GTK_SHARP_2_12 -define:GTK_SHARP_2_14
+	$(CSC) -nowarn:0612 -debug -unsafe -out:$(ASSEMBLY) -target:library $(references) $(csc_build_sources) $(GENERATED_SOURCES) $(plugin_csfiles) $(WIN64DEFINES) -define:GTK_SHARP_2_6 -define:GTK_SHARP_2_8 -define:GTK_SHARP_2_10 -define:GTK_SHARP_2_12 -define:GTK_SHARP_2_14
 
 plugins-update:
 	$(MAKE) -C coreplugins plugins-update
diff --git a/gstreamer-sharp/glib-sharp/Value.cs b/gstreamer-sharp/glib-sharp/Value.cs
index 8d248141bf..5431a8a62a 100755
--- a/gstreamer-sharp/glib-sharp/Value.cs
+++ b/gstreamer-sharp/glib-sharp/Value.cs
@@ -440,10 +440,17 @@ namespace Gst.GLib {
 					return (long) this;
 				else if (type == GType.UInt64.Val)
 					return (ulong) this;
+#if WIN64LONGS
+				else if (type == GType.Long.Val)
+					return g_value_get_long (ref this);
+				else if (type == GType.ULong.Val)
+					return g_value_get_ulong (ref this);
+#else
 				else if (type == GType.Long.Val)
 					return g_value_get_long (ref this).ToInt64 ();
 				else if (type == GType.ULong.Val)
 					return g_value_get_ulong (ref this).ToUInt64 ();
+#endif
 				else if (GType.Is (type, GType.Enum) ||
 					 GType.Is (type, GType.Flags))
 					return ToEnum ();
@@ -487,10 +494,17 @@ namespace Gst.GLib {
 					g_value_set_int64 (ref this, (long) value);
 				else if (type == GType.UInt64.Val)
 					g_value_set_uint64 (ref this, (ulong) value);
+#if WIN64LONGS
+				else if (type == GType.Long.Val)
+					g_value_set_long (ref this, ((IConvertible)value).ToInt32 (null));
+				else if (type == GType.ULong.Val)
+					g_value_set_ulong (ref this, ((IConvertible)value).ToUInt32 (null));
+#else
 				else if (type == GType.Long.Val)
 					g_value_set_long (ref this, new IntPtr (((IConvertible)value).ToInt64 (null)));
 				else if (type == GType.ULong.Val)
 					g_value_set_ulong (ref this, new UIntPtr (((IConvertible)value).ToUInt64 (null)));
+#endif
 				else if (GType.Is (type, GType.Enum))
 					g_value_set_enum (ref this, (int)value);
 				else if (GType.Is (type, GType.Flags))
@@ -610,11 +624,20 @@ namespace Gst.GLib {
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern void g_value_set_uint64 (ref Value val, ulong data);
 
+                /* Windows on x86-64 has 32 bit longs */
+#if WIN64LONGS
+		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
+		static extern void g_value_set_long (ref Value val, int data);
+
+		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
+		static extern void g_value_set_ulong (ref Value val, uint data);
+#else
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern void g_value_set_long (ref Value val, IntPtr data);
 
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern void g_value_set_ulong (ref Value val, UIntPtr data);
+#endif
 
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern void g_value_set_object (ref Value val, IntPtr data);
@@ -663,11 +686,20 @@ namespace Gst.GLib {
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern ulong g_value_get_uint64 (ref Value val);
 
+                /* Windows on x86-64 has 32 bit longs */
+#if WIN64LONGS
+		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
+		static extern int g_value_get_long (ref Value val);
+
+		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
+		static extern uint g_value_get_ulong (ref Value val);
+#else
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern IntPtr g_value_get_long (ref Value val);
 
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern UIntPtr g_value_get_ulong (ref Value val);
+#endif
 
 		[DllImport ("libgobject-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
 		static extern IntPtr g_value_get_object (ref Value val);