diff --git a/test/zdtm.sh b/test/zdtm.sh
index bd2c2f1e7..5f53f6db0 100755
--- a/test/zdtm.sh
+++ b/test/zdtm.sh
@@ -420,7 +420,7 @@ start_test()
 	[ -z "$PIDNS" ] || cd -
 
 	PID=`cat "$TPID"` || return 1
-	if ! ps -p $PID ; then
+	if ! kill -0 $PID ; then
 		echo "Test failed to start"
 		return 1
 	fi