diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index 8272289..cc023b3 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -198,6 +198,8 @@
 		u_int8_t key_len;
 		u_int8_t key[MAX_A5_KEY_LEN];
 	} encr;
+	/* Are we part of a special "silent" call */
+	int silent_call;
 
 	/* AMR bits */
 	struct gsm48_multi_rate_conf mr_conf;
diff --git a/openbsc/src/chan_alloc.c b/openbsc/src/chan_alloc.c
index 8141e47..48f87f2 100644
--- a/openbsc/src/chan_alloc.c
+++ b/openbsc/src/chan_alloc.c
@@ -302,6 +302,8 @@
 	for (i = 0; i < ARRAY_SIZE(lchan->neigh_meas); i++)
 		lchan->neigh_meas[i].arfcn = 0;
 
+	lchan->silent_call = 0;
+
 	/* FIXME: ts_free() the timeslot, if we're the last logical
 	 * channel using it */
 }
diff --git a/openbsc/src/silent_call.c b/openbsc/src/silent_call.c
index 82b6563..500d187 100644
--- a/openbsc/src/silent_call.c
+++ b/openbsc/src/silent_call.c
@@ -53,6 +53,7 @@
 	case GSM_PAGING_SUCCEEDED:
 		DEBUGPC(DSMS, "success, using Timeslot %u on ARFCN %u\n",
 			lchan->ts->nr, lchan->ts->trx->arfcn);
+		lchan->silent_call = 1;
 		/* increment lchan reference count */
 		dispatch_signal(SS_SCALL, S_SCALL_SUCCESS, &sigdata);
 		use_lchan(lchan);
@@ -86,7 +87,10 @@
 	if (!lchan)
 		return -EINVAL;
 
-	/* FIXME: did we actually establish a silent call for this guy? */
+	/* did we actually establish a silent call for this guy? */
+	if (!lchan->silent_call)
+		return -EINVAL;
+
 	put_lchan(lchan);
 
 	return 0;