diff --git a/library/RSL_Types.ttcn b/library/RSL_Types.ttcn
index 46fa669..67e4dc9 100644
--- a/library/RSL_Types.ttcn
+++ b/library/RSL_Types.ttcn
@@ -996,7 +996,7 @@
 						 uint32_t remote_ip, uint16_t remote_port,
 						 uint7_t rtp_pt2) := {
 		msg_disc := ts_RSL_MsgDisc(RSL_MDISC_IPACCESS, false),
-		msg_type := RSL_MT_IPAC_CRCX_NACK,
+		msg_type := RSL_MT_IPAC_MDCX_ACK,
 		ies := {
 			t_RSL_IE(RSL_IE_CHAN_NR, RSL_IE_Body:{chan_nr := chan_nr}),
 			/* optional */