diff --git a/cmake/FindGDAL.cmake b/cmake/FindGDAL.cmake
index e507c4a..0631367 100644
--- a/cmake/FindGDAL.cmake
+++ b/cmake/FindGDAL.cmake
@@ -135,7 +135,8 @@ ELSE(WIN32)
         ENDIF (GDAL_LIB_NAME_WITH_PREFIX)
 
         IF (APPLE)
-          SET(GDAL_LIBRARY ${GDAL_LINK_DIRECTORIES}/lib${GDAL_LIB_NAME}.dylib CACHE STRING INTERNAL)
+          SET(GDAL_LIBRARY ${GDAL_LINK_DIRECTORIES}/lib${GDAL_LIB_NAME}.dylib
+            CACHE FILEPATH "Path to GDAL library." FORCE)
         ELSE (APPLE)
           SET(GDAL_LIBRARY ${GDAL_LINK_DIRECTORIES}/lib${GDAL_LIB_NAME}.so CACHE STRING INTERNAL)
         ENDIF (APPLE)
diff --git a/cmake/FindGEOS.cmake b/cmake/FindGEOS.cmake
index eb497fc..38acf5d 100644
--- a/cmake/FindGEOS.cmake
+++ b/cmake/FindGEOS.cmake
@@ -132,7 +132,8 @@ ELSE(WIN32)
         #MESSAGE("DBG  GEOS_LIB_NAME=${GEOS_LIB_NAME}")
 
         IF (APPLE)
-          SET(GEOS_LIBRARY ${GEOS_LINK_DIRECTORIES}/lib${GEOS_LIB_NAME}.dylib CACHE STRING INTERNAL)
+          SET(GEOS_LIBRARY ${GEOS_LINK_DIRECTORIES}/lib${GEOS_LIB_NAME}.dylib
+            CACHE FILEPATH "Path to GEOS library." FORCE)
         ELSE (APPLE)
           SET(GEOS_LIBRARY ${GEOS_LINK_DIRECTORIES}/lib${GEOS_LIB_NAME}.so CACHE STRING INTERNAL)
         ENDIF (APPLE)