diff --git a/modules_k/acc/acc_logic.c b/modules_k/acc/acc_logic.c
index d6e6d53..6cac79d 100644
--- a/modules_k/acc/acc_logic.c
+++ b/modules_k/acc/acc_logic.c
@@ -493,6 +493,8 @@ int acc_api_exec(struct sip_msg *rq, acc_engine_t *eng,
 
 static void tmcb_func( struct cell* t, int type, struct tmcb_params *ps )
 {
+	LM_DBG("acc callback called for t(%p) event type %d, reply code %d\n",
+			t, type, ps->code);
 	if (type&TMCB_RESPONSE_OUT) {
 		acc_onreply( t, ps->req, ps->rpl, ps->code);
 	} else if (type&TMCB_E2EACK_IN) {