John Mayer and Jennifer Aniston
Tzirel Kaminetzky; Lester Cohen/WireImage
10/16/2008 at 02:10 PM EDT
spent his birthday with a very special friend: Jennifer Aniston
The couple, who broke up in August, reconnected last weekend in New York
, and were then spotted together in L.A. celebrating Mayer's 31st birthday on Wednesday night.
The bash was held at the Grand Havana Room, a members-only restaurant and cigar club.
After stopping by a party for pal David Arquette's new clothing line, called Propr, Aniston, 39, met up with the group, staying past midnight to ring in Mayer's birthday.
"They seemed to be having a great time," a source tells PEOPLE. "They were sitting next to each other. They're a very good-looking couple and seemed happy together."
It was their second outing in L.A. this week, following a dinner with friends the night before at the Sunset Towers.
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