diff --git a/build/mkrelease b/build/mkrelease
index dcd32b2105..0b8554061e 100755
--- a/build/mkrelease
+++ b/build/mkrelease
@@ -64,6 +64,7 @@ echo "Rolling up $OL_STRING ..."
 tar cf $RELNAME.tar $RELNAME
 gzip -9 -c $RELNAME.tar > $RELNAME.tgz
 md5 $RELNAME.tgz > $RELNAME.md5
+sha1 $RELNAME.tgz > $RELNAME.sha1
 rm -f $RELNAME.tar
 
 ls -l $RELNAME.*