proper reauthentication:

IKE_SA is closed completely before the new is initiated, 
  resolves some issues when a dynamic IP is requested from a pool

src/charon/processing/jobs/rekey_ike_sa_job.c

@@ -74,7 +74,7 @@ static void execute(private_rekey_ike_sa_job_t *this)
 	{
 		if (this->reauth)
 		{
-			ike_sa->reestablish(ike_sa);
+			status = ike_sa->reestablish(ike_sa);
 		}
 		else
 		{