diff --git a/lib/csharp/Makefile.am b/lib/csharp/Makefile.am
index bf02c87..1fd5462 100644
--- a/lib/csharp/Makefile.am
+++ b/lib/csharp/Makefile.am
@@ -52,6 +52,7 @@
             src/Transport/TBufferedTransport.cs \
             src/Transport/TTransport.cs \
             src/Transport/TSocket.cs \
+            src/Transport/TSocketVersionizer.cs \
             src/Transport/TTransportException.cs \
             src/Transport/TStreamTransport.cs \
             src/Transport/TFramedTransport.cs \