Income tax refund

Dear Friends,

One of my freind had made a mistake during e filing of his Income Tax returns for AY 2012-13. First of all he had filed the return after due date. He is a salaried person but during the year he got some commision for a car deal from a company after deducting TDS. During the Return filing he had not disclosed this other income and TDS too. 

Now he had discovered that if he had disclosed this Commision in ITR he would have claimed refund for the TDS deducted.

Is there any way to claim refund as as per my knowledge he cannot revise the return as he has filed return after due date.

Pls Advise....