Now that Karan Johar is back in town after a long schedule of his film in Bangkok, preparations have begun for his 40th birthday bash on May 25

His close pals are gearing up for the filmmaker's big day. A birdie chirps that different themes have been suggested and plans are to make it a party to remember with the who's who of Bollywood on the guest list.

One of the suggestions is to have a Naughty@40 bash. Hmmmm...