$NetBSD$

--- tools/backupdir.orig	2000-02-25 01:37:28.000000000 +0300
+++ tools/backupdir	2010-01-11 14:21:42.000000000 +0300
@@ -25,7 +25,7 @@
 	    revisions=$pwd/$subdir-$date.revisions.gz
 
 	    # If there is no backup, make one
-	    if [ z"$olddiff" == z  ] ; then 
+	    if [ z"$olddiff" = z  ] ; then 
 	    	echo "No backup for $dir/$subdir, making one"
 		(cd $dir/$subdir; cvs diff -u -N . 2> /dev/null |
 		    gzip -9 > $diff)
