--- channels/chan_iax2.c.orig	2012-03-13 15:40:27.000000000 +0200
+++ channels/chan_iax2.c	2012-03-13 15:41:39.000000000 +0200
@@ -13151,6 +13151,8 @@
 			trunkfreq = atoi(v->value);
 			if (trunkfreq < 10)
 				trunkfreq = 10;
+			if (timer)
+				ast_timer_set_rate(timer, 1000 / trunkfreq);
 		} else if (!strcasecmp(v->name, "trunkmtu")) {
 			mtuv = atoi(v->value);
 			if (mtuv  == 0 )