diff --git a/configure b/configure
index 34195336594..3f4f3c27299 100755
--- a/configure
+++ b/configure
@@ -3863,8 +3863,8 @@ echo "configure:3858: checking for libIDL - version >= $min_libIDL_version" >&5
     LIBIDL_LIBS=`$LIBIDL_CONFIG $libIDL_config_args --libs`
     # hack to allow us to keep using libIDL 0.6.3-0.6.7. Anyone may remove
     # this after we start requiring libIDL 0.6.8 or anything higher
-    LIBIDL_CFLAGS='$GLIB_CFLAGS $LIBIDL_CFLAGS'
-    LIBIDL_LIBS='$GLIB_LIBS $LIBIDL_LIBS'
+    LIBIDL_CFLAGS="$GLIB_CFLAGS $LIBIDL_CFLAGS"
+    LIBIDL_LIBS="$GLIB_LIBS $LIBIDL_LIBS"
     libIDL_config_major_version=`$LIBIDL_CONFIG $libIDL_config_args --version | \
            sed 's/\([0-9]*\).\([0-9]*\).\([0-9]*\)/\1/'`
     libIDL_config_minor_version=`$LIBIDL_CONFIG $libIDL_config_args --version | \