diff --git a/library/GSM_Types.ttcn b/library/GSM_Types.ttcn
index 9710c26..bcd0afb 100644
--- a/library/GSM_Types.ttcn
+++ b/library/GSM_Types.ttcn
@@ -14,6 +14,7 @@
 
 import from General_Types all;
 import from Osmocom_Types all;
+import from Misc_Helpers all;
 
 type integer GsmArfcn (0..1023);
 type integer UmtsArfcn (0..16383);
@@ -86,11 +87,10 @@
 	case (CS2) { return 32 }
 	case (CS3) { return 38 }
 	case (CS3) { return 52 }
-	case else {
-		setverdict(fail, "Invalid GPRS CS ", cs);
-		mtc.stop;
-		}
 	}
+	Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail,
+				log2str("Invalid GPRS CS ", cs));
+	return 0;
 }
 
 const GprsTlli TLLI_UNUSED := 'FFFFFFFF'O;