diff --git a/stepmania/src/Makefile.am b/stepmania/src/Makefile.am
index 942d2d416a..b51d1d8d56 100644
--- a/stepmania/src/Makefile.am
+++ b/stepmania/src/Makefile.am
@@ -261,7 +261,8 @@ RageSurface_Save_BMP.cpp RageSurface_Save_BMP.h \
 RageTextureID.cpp RageTextureID.h RageTextureManager.cpp RageTextureManager.h RageThreads.cpp RageThreads.h \
 RageTimer.cpp RageTimer.h RageTypes.h RageUtil.cpp RageUtil.h RageUtil_CharConversions.cpp RageUtil_CharConversions.h \
 RageUtil_BackgroundLoader.cpp RageUtil_BackgroundLoader.h RageUtil_FileDB.cpp RageUtil_FileDB.h RageUtil_CircularBuffer.h \
-RageUtil_AutoPtr.h
+RageUtil_AutoPtr.h \
+RageUtil_WorkerThread.cpp RageUtil_WorkerThread.h
 
 Actors = \
 Actor.cpp Actor.h ActorCollision.h ActorFrame.cpp ActorFrame.h \