diff --git a/include/openbsc/gsm_subscriber.h b/include/openbsc/gsm_subscriber.h
index 8dcde3e..e0c621b 100644
--- a/include/openbsc/gsm_subscriber.h
+++ b/include/openbsc/gsm_subscriber.h
@@ -28,12 +28,14 @@
 enum gsm_subscriber_field {
 	GSM_SUBSCRIBER_IMSI,
 	GSM_SUBSCRIBER_TMSI,
+	GSM_SUBSCRIBER_EXTENSION,
 };
 
 struct gsm_subscriber *subscr_get(struct gsm_subscriber *subscr);
 struct gsm_subscriber *subscr_put(struct gsm_subscriber *subscr);
 struct gsm_subscriber *subscr_get_by_tmsi(const char *tmsi);
 struct gsm_subscriber *subscr_get_by_imsi(const char *imsi);
+struct gsm_subscriber *subscr_get_by_extension(const char *ext);
 int subscr_update(struct gsm_subscriber *s, struct gsm_bts *bts);
 
 /* internal */
diff --git a/src/db.c b/src/db.c
index 50459cf..b538d5d 100644
--- a/src/db.c
+++ b/src/db.c
@@ -119,6 +119,7 @@
 		"id INTEGER PRIMARY KEY AUTOINCREMENT, "
 		"created TIMESTAMP NOT NULL, "
 		"updated TIMESTAMP NOT NULL, "
+		"name TEXT, "
 		"imei NUMERIC UNIQUE NOT NULL"
 		")"
 	);
@@ -219,6 +220,15 @@
 		);
 		free(quoted);
 		break;
+	case GSM_SUBSCRIBER_EXTENSION:
+		dbi_conn_quote_string_copy(conn, id, &quoted);
+		result = dbi_conn_queryf(conn,
+			"SELECT * FROM Subscriber "
+			"WHERE extension = %s ",
+			quoted
+		);
+		free(quoted);
+		break;
 	default:
 		printf("DB: Unknown query selector for Subscriber.\n");
 		return NULL;
diff --git a/src/gsm_subscriber.c b/src/gsm_subscriber.c
index 390979b..d4dfea4 100644
--- a/src/gsm_subscriber.c
+++ b/src/gsm_subscriber.c
@@ -78,6 +78,18 @@
 	return db_get_subscriber(GSM_SUBSCRIBER_IMSI, imsi);
 }
 
+struct gsm_subscriber *subscr_get_by_extension(const char *ext)
+{
+	struct gsm_subscriber *subscr;
+
+	llist_for_each_entry(subscr, &active_subscribers, entry) {
+		if (strcmp(subscr->extension, ext) == 0)
+			return subscr_get(subscr);
+	}
+
+	return db_get_subscriber(GSM_SUBSCRIBER_EXTENSION, ext);
+}
+
 int subscr_update(struct gsm_subscriber *s, struct gsm_bts *bts)
 {
 	return db_sync_subscriber(s);