diff --git a/openbsc/src/gprs/gprs_gmm.c b/openbsc/src/gprs/gprs_gmm.c
index 07fd1dc..04f75cf 100644
--- a/openbsc/src/gprs/gprs_gmm.c
+++ b/openbsc/src/gprs/gprs_gmm.c
@@ -1639,7 +1639,7 @@
 {
 	struct sgsn_pdp_ctx *pdp;
 
-	LOGMMCTXP(LOGL_DEBUG, mmctx, "Using GGSN %d\n", ggsn->id);
+	LOGMMCTXP(LOGL_DEBUG, mmctx, "Using GGSN %u\n", ggsn->id);
 	ggsn->gsn = sgsn->gsn;
 	pdp = sgsn_create_pdp_ctx(ggsn, mmctx, req_nsapi, tp);
 	if (!pdp)
diff --git a/openbsc/src/gprs/sgsn_vty.c b/openbsc/src/gprs/sgsn_vty.c
index 70d299b..f818221 100644
--- a/openbsc/src/gprs/sgsn_vty.c
+++ b/openbsc/src/gprs/sgsn_vty.c
@@ -167,11 +167,11 @@
 		vty_out(vty, " ! apn * ggsn 0%s", VTY_NEWLINE);
 	llist_for_each_entry(actx, &sgsn_apn_ctxts, list) {
 		if (strlen(actx->imsi_prefix) > 0)
-			vty_out(vty, " apn %s imsi-prefix %s ggsn %d%s",
+			vty_out(vty, " apn %s imsi-prefix %s ggsn %u%s",
 				actx->name, actx->imsi_prefix, actx->ggsn->id,
 				VTY_NEWLINE);
 		else
-			vty_out(vty, " apn %s ggsn %d%s", actx->name,
+			vty_out(vty, " apn %s ggsn %u%s", actx->name,
 				actx->ggsn->id, VTY_NEWLINE);
 	}