diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b9d6fc55..15ceb2177 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -227,6 +227,7 @@ INCLUDE_DIRECTORIES( BEFORE
   include
   ${CMAKE_CURRENT_BINARY_DIR}
   ${CMAKE_CURRENT_BINARY_DIR}/include
+  contrib/
 )
 
 LIST(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake-modules" )