diff --git a/lib/csharp/Makefile.am b/lib/csharp/Makefile.am
index b99674c..cbc003b 100644
--- a/lib/csharp/Makefile.am
+++ b/lib/csharp/Makefile.am
@@ -92,4 +92,5 @@
              src/Thrift.sln \
              src/Thrift.WP7.csproj \
              src/Properties/AssemblyInfo.WP7.cs \
+             src/Transport/TSilverlightSocket.cs \
              test