diff --git a/FindQwtPolar.cmake b/FindQwtPolar.cmake
index 033607d..0fad8cd 100644
--- a/FindQwtPolar.cmake
+++ b/FindQwtPolar.cmake
@@ -42,9 +42,9 @@ ENDIF (QWTPOLAR_INCLUDE_DIR AND QWTPOLAR_LIBRARY)
 
 IF (QWTPOLAR_FOUND)
   FILE(READ ${QWTPOLAR_INCLUDE_DIR}/qwt_polar_global.h qwt_header)
-  STRING(REGEX REPLACE "^.*QWTPOLAR_VERSION_STR +\"([^\"]+)\".*$" "\\1" QWTPOLAR_VERSION_STR "${qwt_header}")
+  STRING(REGEX REPLACE "^.*QWT_POLAR_VERSION_STR +\"([^\"]+)\".*$" "\\1" QWT_POLAR_VERSION_STR "${qwt_header}")
   IF (NOT QWTPOLAR_FIND_QUIETLY)
-    MESSAGE(STATUS "Found QwtPolar: ${QWTPOLAR_LIBRARY} (${QWTPOLAR_VERSION_STR})")
+    MESSAGE(STATUS "Found QwtPolar: ${QWTPOLAR_LIBRARY} (${QWT_POLAR_VERSION_STR})")
   ENDIF (NOT QWTPOLAR_FIND_QUIETLY)
 ELSE (QWTPOLAR_FOUND)
   IF (QWTPOLAR_FIND_REQUIRED)