diff --git a/openbsc/src/nat/bsc_sccp.c b/openbsc/src/nat/bsc_sccp.c
index 97a4f12..33ab51d 100644
--- a/openbsc/src/nat/bsc_sccp.c
+++ b/openbsc/src/nat/bsc_sccp.c
@@ -55,7 +55,7 @@
 /* copied from sccp.c */
 static int assign_src_local_reference(struct sccp_source_reference *ref, struct bsc_nat *nat)
 {
-	static u_int32_t last_ref = 0x50000;
+	static uint32_t last_ref = 0x50000;
 	int wrapped = 0;
 
 	do {