Aamir'll sing again in 'Dhoom 3' after Gulam

After singing 'Aati Kya Khandala' for Jatin-Lalit in Ghulam, Bollywood's Mr. Perfectionist Aamir Khan is all set to lend his voice to Dhoom 3 theme song. For this composer Pritam Chakraborty has been clearly instructed by producer Aditya Chopra to compose a tune, which will match Aamir's character in the movie. According to reports Pritam has also been asked to complete all his other assignments