diff --git a/CMakeLists.txt b/CMakeLists.txt
index 11927c11..005d26bf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -108,6 +108,7 @@ if (ISLE_BUILD_LIB)
     LEGO1/mxcontrolpresenter.cpp
     LEGO1/mxcore.cpp
     LEGO1/mxcriticalsection.cpp
+    LEGO1/mxdirectdraw.cpp
     LEGO1/mxdiskstreamcontroller.cpp
     LEGO1/mxdiskstreamprovider.cpp
     LEGO1/mxdsaction.cpp