diff --git a/tools/mergedirs b/tools/mergedirs
index 33bcbdaa..883e6f17 100755
--- a/tools/mergedirs
+++ b/tools/mergedirs
@@ -24,7 +24,7 @@ MODULES=`for a in $@ ; do
 		$cpp -U unix -D MACROS_ONLY -I $OBJDIR - |
 		sed "/^[ ]*\$/d;/^#/d;s@\\(.*\\)@\\1 $a/\\1@"
 		done |
-	sort +0 -1 -u |
+	sort -k1,1 -u |
 	cut -d ' ' -f 2`
 rm -rf $LIBDIR $CONFDIR
 mkdir -p $LIBDIR $CONFDIR