diff --git a/library/BSSMAP_Templates.ttcn b/library/BSSMAP_Templates.ttcn
index 5d2bff2..5d13899 100644
--- a/library/BSSMAP_Templates.ttcn
+++ b/library/BSSMAP_Templates.ttcn
@@ -665,8 +665,8 @@
 }
 
 private function f_enc_mcc_mnc(GsmMcc mcc, GsmMnc mnc) return OCT3 {
-	if (mnc[0] == 'f'H) {
-		return hex2oct(mcc[1] & mcc[0] & mnc[0] & mcc[2] & mnc[2] & mnc[1]);
+	if (lengthof(mnc) == 2) {
+		return hex2oct(mcc[1] & mcc[0] & 'F'H & mcc[2] & mnc[1] & mnc[0]);
 	} else {
 		return hex2oct(mcc[1] & mcc[0] & mnc[2] & mcc[2] & mnc[1] & mnc[0]);
 	}