It was meant to be a formal dinner, but Adnan Sami's birthday party turned into a musical night with singers like Mika and Sunidhi Chauhan jamming evergreen Bollywood hits.

Sami, known for numbers like "Bheegi bheegi raaton mein" and "Lift kara de", turned 39 Aug 15. He threw a bash Aug 18, the same day as a party at Mukesh and Tina Ambani's grand residence Antilla.

Even though the Bachchan family could not attend Sami's party due to their prior commitment to the Ambanis, the singer was happy with a great turnout at his bash at his Lokhandwala residence.

Few guests from the Ambani's list are said to have hop-skipped and jumped over to Sami's party too.

According to one of Sami's prominent invitees: "It was a fun evening. But more than fun, it was a musical evening.

"While guests like Rishi Kapoor, Subhash Ghai and Rakesh Roshan divided their time between the Ambanis and the Samis, the musical brigade namely Mika, Shaan, Sunidhi Chauhan and her husband Hitesh, Salim-Suleiman, Anees Bazmi Sajid-Wajid, Raghav Sachar and G.V.Prakash (of 'Aa ante amblapuram') turned the formal sit-in dinner into a jackets-off musical evening."

There was also an impromptu antakshari session.

"Mika initiated the idea of an antakshari based on the songs of all the filmmakers, actors and musicians who were present at the party. It started as a spontaneous outburst of joyous singing, but quickly became a homage to the music of Rishi Kapoor, Subhash Ghai, Rakesh Roshan, Anees Bazmi and Adnan Sami. Rishi, Subhash Ghai and Rishi Kapoor also joined in," said a guest.

The music, dancing and partying went on until 5 a.m.

Adnan was happy too.

"It was an amazing evening. I expected it to be enjoyable. But not so musical. We sang all night," said the singer, who even cut a piano -shaped cake.