diff --git a/pcu/RAW_NS.ttcn b/pcu/RAW_NS.ttcn
index ec484ba..4300376 100644
--- a/pcu/RAW_NS.ttcn
+++ b/pcu/RAW_NS.ttcn
@@ -38,7 +38,7 @@
 		}
 }
 
-function f_init_ns_codec(integer idx := 0, float guard_secs := 60.0) runs on RAW_NS_CT {
+function f_init_ns_codec(integer idx := 0, float guard_secs := 60.0, integer tc_offset := 0) runs on RAW_NS_CT {
 	var Result res;
 
 	if (not g_T_guard.running) {
@@ -51,7 +51,7 @@
 		g_nsconfig[idx] := mp_nsconfig;
 		/* adjust those parts different for each NS-VC */
 		g_nsconfig[idx].nsvci := mp_nsconfig.nsvci + idx;
-		g_nsconfig[idx].local_udp_port := mp_nsconfig.local_udp_port + idx;
+		g_nsconfig[idx].local_udp_port := mp_nsconfig.local_udp_port + idx + tc_offset;
 	}
 
 	map(self:NSCP[idx], system:NSCP);