nat: Keep track of the error message.
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat.c b/openbsc/src/osmo-bsc_nat/bsc_nat.c
index ba27341..3112ff3 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat.c
@@ -563,10 +563,11 @@
 {
 	struct bsc_connection *bsc;
 	const uint8_t *paging_start;
-	int paging_length, i;
+	int paging_length, i, ret;
 
-	if (bsc_nat_find_paging(msg, &paging_start, &paging_length) != 0) {
-		LOGP(DNAT, LOGL_ERROR, "Could not parse paging message.\n");
+	ret = bsc_nat_find_paging(msg, &paging_start, &paging_length);
+	if (ret != 0) {
+		LOGP(DNAT, LOGL_ERROR, "Could not parse paging message: %d\n", ret);
 		return;
 	}