diff --git a/examples/osgcluster/CMakeLists.txt b/examples/osgcluster/CMakeLists.txt
index 615231347..d003e4f33 100644
--- a/examples/osgcluster/CMakeLists.txt
+++ b/examples/osgcluster/CMakeLists.txt
@@ -4,5 +4,9 @@ SET(TARGET_SRC
     osgcluster.cpp
 )
 
+IF   (WIN32)
+   SET(TARGET_EXTERNAL_LIBRARIES ws2_32)
+ENDIF(WIN32)
+
 #### end var setup  ###
 SETUP_EXAMPLE(osgcluster)