diff --git a/CMakeLists.txt b/CMakeLists.txt
index b6e0dd509..80e3aeb15 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -179,13 +179,16 @@ ENDIF("${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_BINARY_DIR}")
 
 SET(CMAKE_DEBUG_POSTFIX  "d")
 
-SET(LIB_POSTFIX "")
 IF(UNIX AND NOT WIN32 AND NOT APPLE)
   IF(CMAKE_SIZEOF_VOID_P MATCHES "8")
-      SET(LIB_POSTFIX "64")
+      SET(LIB_POSTFIX "64" CACHE STRING "suffix for 32/64 dir placement")
+      MARK_AS_ADVANCED(LIB_POSTFIX)
   ENDIF(CMAKE_SIZEOF_VOID_P MATCHES "8")
 ENDIF(UNIX AND NOT WIN32 AND NOT APPLE)
-
+IF(NOT DEFINED LIB_POSTFIX)
+    SET(LIB_POSTFIX "")
+ENDIF(NOT DEFINED LIB_POSTFIX)
+    
 #SET(OUTPUT_BINDIR ${PROJECT_BINARY_DIR}/bin/${CMAKE_SYSTEM_NAME})
 SET(OUTPUT_BINDIR ${PROJECT_BINARY_DIR}/bin)
 MAKE_DIRECTORY(${OUTPUT_BINDIR})