diff --git a/remsim/RSPRO_Server.ttcn b/remsim/RSPRO_Server.ttcn
index 635629fb8..bb11689de 100644
--- a/remsim/RSPRO_Server.ttcn
+++ b/remsim/RSPRO_Server.ttcn
@@ -46,6 +46,7 @@ private altstep as_rspro_srv_Tguard() runs on rspro_server_CT {
 
 altstep as_ignore_id_ack(integer i) runs on rspro_server_CT {
 	[] RSPRO_SRV[i].receive(tr_ASP_IPA_EV(ASP_IPA_EVENT_ID_ACK)) { repeat; }
+	[] RSPRO_SRV[i].receive(tr_ASP_IPA_EV(ASP_IPA_EVENT_ID_RESP)) { repeat; }
 }