--- zzzz-none-000/linux-2.6.19.2/net/sched/sch_tbf.c	2007-01-10 19:10:37.000000000 +0000
+++ davinci-8020-5505/linux-2.6.19.2/net/sched/sch_tbf.c	2008-04-03 14:19:26.000000000 +0000
@@ -340,7 +340,7 @@
 	if (max_size < 0)
 		goto done;
 
-	if (qopt->limit > 0) {
+	if (qopt->limit > 0 && q->qdisc == &noop_qdisc) {
 		if ((child = tbf_create_dflt_qdisc(sch->dev, qopt->limit)) == NULL)
 			goto done;
 	}