diff --git a/src/osgProducer/Viewer.cpp b/src/osgProducer/Viewer.cpp
index 59961400b..0cb5bf6c1 100644
--- a/src/osgProducer/Viewer.cpp
+++ b/src/osgProducer/Viewer.cpp
@@ -1,5 +1,6 @@
 #include <osg/LightSource>
 #include <osg/ApplicationUsage>
+#include <osg/AlphaFunc>
 #include <osg/io_utils>
 
 #include <osgUtil/UpdateVisitor>