diff --git a/openbsc/src/gsm_04_11.c b/openbsc/src/gsm_04_11.c
index 5070b54..246847b 100644
--- a/openbsc/src/gsm_04_11.c
+++ b/openbsc/src/gsm_04_11.c
@@ -175,6 +175,10 @@
 		/* FIXME: implementation */
 		DEBUGP(DSMS, "VPI enhanced not implemented yet\n");
 		break;
+	case GSM340_TP_VPF_NONE:
+		/* Default validity: two days */
+		minutes = 24 * 60 * 2;
+		break;
 	}
 	return minutes;
 }
@@ -383,6 +387,9 @@
 		sms_vp = smsp;
 		smsp += 7;
 		break;
+	case GSM340_TP_VPF_NONE:
+		sms_vp = 0;
+		break;
 	default:
 		DEBUGP(DSMS, "SMS Validity period not implemented: 0x%02x\n",
 				sms_vpf);