--- /usr/share/cmake-2.8/Modules/FindBZip2.cmake	2013-07-02 15:41:39.000000000 +0200
+++ cmake/FindBZip2.cmake	2013-12-05 09:07:47.000000000 +0100
@@ -39,6 +39,9 @@
 if (BZIP2_INCLUDE_DIR AND EXISTS "${BZIP2_INCLUDE_DIR}/bzlib.h")
     file(STRINGS "${BZIP2_INCLUDE_DIR}/bzlib.h" BZLIB_H REGEX "bzip2/libbzip2 version [0-9]+\\.[^ ]+ of [0-9]+ ")
     string(REGEX REPLACE ".* bzip2/libbzip2 version ([0-9]+\\.[^ ]+) of [0-9]+ .*" "\\1" BZIP2_VERSION_STRING "${BZLIB_H}")
+else ()
+    unset(BZIP2_FOUND CACHE)
+    return()
 endif ()
 
 # handle the QUIETLY and REQUIRED arguments and set BZip2_FOUND to TRUE if