diff --git a/openbsc/src/gsm_data.c b/openbsc/src/gsm_data.c
index 27d0732..705c107 100644
--- a/openbsc/src/gsm_data.c
+++ b/openbsc/src/gsm_data.c
@@ -248,7 +248,7 @@
 }
 
 struct gsm_network *gsm_network_init(u_int16_t country_code, u_int16_t network_code,
-				     int (*mncc_recv)(struct gsm_network *, int, void *))
+				     int (*mncc_recv)(struct gsm_network *, struct msgb *))
 {
 	struct gsm_network *net;