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JENNIFER ANISTON spent her 39th birthday on Monday in Canada working on her new film 'Traveling,' but did manage to squeeze in a mini-celebration according to People. The cast and crew of the romantic drama, also starring AARON ECKHART, treated the actress to a "giant ice cream cake," according to a source. "The crew all gathered around and sang a rousing rendition of 'Happy Birthday.' [There were] hugs and kisses for everyone, from everyone."

The "Friends" alum also celebrated at a local restaurant just two days before her big day. Twenty of her closest friends were on hand for the bash that lasted until 2:30 a.m. "She had a really good time with all of her friends," an onlooker tells the mag, "and seemingly didn't want the evening to end."