diff --git a/OpenEXR/CMakeLists.txt b/OpenEXR/CMakeLists.txt
index 5bfb3ab03c..8d1ef77617 100644
--- a/OpenEXR/CMakeLists.txt
+++ b/OpenEXR/CMakeLists.txt
@@ -10,7 +10,7 @@ IF (NOT ILMBASE_PACKAGE_PREFIX)
   SET (ILMBASE_PACKAGE_PREFIX ${CMAKE_INSTALL_PREFIX})
 ENDIF ()
 
-ADD_DEFINITIONS (-DILM_IMF_TEST_IMAGEDIR="${CMAKE_SOURCE_DIR}/IlmImfTest/" )
+ADD_DEFINITIONS (-DILM_IMF_TEST_IMAGEDIR="${CMAKE_CURRENT_SOURCE_DIR}/IlmImfTest/" )
 
 IF (NOT WIN32)
   SET ( PTHREAD_LIB pthread )