diff --git a/openbsc/src/gprs/gb_proxy_tlli.c b/openbsc/src/gprs/gb_proxy_tlli.c
index f554db1..91469b0 100644
--- a/openbsc/src/gprs/gb_proxy_tlli.c
+++ b/openbsc/src/gprs/gb_proxy_tlli.c
@@ -309,7 +309,7 @@
 {
 	struct gbproxy_tlli_info *tlli_info;
 	int enable_patching = -1;
-	int tlli_already_known;
+	int tlli_already_known = 0;
 
 	/* Check, whether the IMSI matches */
 	if (gprs_is_mi_imsi(imsi, imsi_len)) {