diff --git a/scripts/git-checkout.sh b/scripts/git-checkout.sh
index fd4425ac4e..56a60193a7 100755
--- a/scripts/git-checkout.sh
+++ b/scripts/git-checkout.sh
@@ -1,12 +1,12 @@
 #!/bin/sh
 
 if test $# -lt 3; then
-	echo "Usage: $0 <tree> <tag> <dir>"
+	echo "Usage: $0 <tree> <committish> <dir>"
 	exit 1
 fi
 
 TREE=$1
-TAG=$2
+COMMITTISH=$2
 DIR=$3
 
 set -e
@@ -15,10 +15,11 @@ if test \! -d $DIR-remote; then
 	rm -rf $DIR-remote $DIR-remote.tmp
 	mkdir -p $DIR-remote.tmp; rmdir $DIR-remote.tmp
 	$GIT clone $TREE $DIR-remote.tmp
-	if test "$TAG" ; then
+	if test "$COMMITTISH" ; then
 		cd $DIR-remote.tmp
+		$GIT fetch origin "$COMMITTISH"
 		$GIT branch -D dummy >/dev/null 2>&1 ||:
-		$GIT checkout -b dummy $TAG
+		$GIT checkout -b dummy FETCH_HEAD
 		cd -
 	fi
 	mv $DIR-remote.tmp $DIR-remote