diff --git a/Modules/FindKDE3.cmake b/Modules/FindKDE3.cmake
index 721f24d80..aeba824b4 100644
--- a/Modules/FindKDE3.cmake
+++ b/Modules/FindKDE3.cmake
@@ -97,10 +97,10 @@ IF (CMAKE_SYSTEM_NAME MATCHES BSD AND CMAKE_COMPILER_IS_GNUCXX)
 ENDIF (CMAKE_SYSTEM_NAME MATCHES BSD AND CMAKE_COMPILER_IS_GNUCXX)
 
 # if no special buildtype is selected, add -O2 as default optimization
-IF (NOT CMAKE_BUILD_TYPE)
+IF (NOT CMAKE_BUILD_TYPE AND CMAKE_COMPILER_IS_GNUCXX)
    SET ( CMAKE_C_FLAGS     "${CMAKE_C_FLAGS} -O2")
    SET ( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O2")
-ENDIF (NOT CMAKE_BUILD_TYPE)
+ENDIF (NOT CMAKE_BUILD_TYPE AND CMAKE_COMPILER_IS_GNUCXX)
 
 
 #SET(CMAKE_SHARED_LINKER_FLAGS "-avoid-version -module -Wl,--no-undefined -Wl,--allow-shlib-undefined")