diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 7c73a7a3bb..f6da05bb0c 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,7 +2,7 @@
 add_subdirectory( pics )
 add_subdirectory( tests )
 
-include_directories( ${KDE4_INCLUDE_DIR} ${QT_INCLUDES} ${BLITZ_INCLUDES} )
+include_directories( ${KDE4_INCLUDE_DIR} ${QT_INCLUDES} ${BLITZ_INCLUDES} ${SOPRANO_INCLUDE_DIR} )
 
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