Fixed bug in ticket #455 in round-robin call ID allocation (thanks Truong Thanh Quang)

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@1821 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjsip/src/pjsua-lib/pjsua_call.c b/pjsip/src/pjsua-lib/pjsua_call.c
index 6cf63f0..ca78745 100644
--- a/pjsip/src/pjsua-lib/pjsua_call.c
+++ b/pjsip/src/pjsua-lib/pjsua_call.c
@@ -224,7 +224,7 @@
     if (pjsua_var.next_call_id >= (int)pjsua_var.ua_cfg.max_calls || 
 	pjsua_var.next_call_id < 0)
     {
-	cid = 0;
+	pjsua_var.next_call_id = 0;
     }
 
     for (cid=pjsua_var.next_call_id;