smpp: In case we know the receiver set the context for logging
diff --git a/openbsc/src/libmsc/smpp_openbsc.c b/openbsc/src/libmsc/smpp_openbsc.c
index 9d2183a..e309377 100644
--- a/openbsc/src/libmsc/smpp_openbsc.c
+++ b/openbsc/src/libmsc/smpp_openbsc.c
@@ -66,6 +66,8 @@
 		break;
 	}
 
+	/* tag the context in case we know it */
+	log_set_context(BSC_CTX_SUBSCR, subscr);
 	return subscr;
 }