IT Returns for Salaried employee with less than 5 Lakhs income

Hi Friends

My brother is doing his first job and salary is well below 5 Lakhs. He paid around 1350/- tax for the FY 2012-13. I read online that IT returns is not mandatory for people with less than 5 Lakhs income, but is it okay if he my brother still chooses to the file the IT Returns? 

Thanks in advance

Sam