Amanda Bynes decided retirement was for the birds. Just weeks after announcing that she'd quit acting, the 24-year-old is back in the game, RadarOnline.com has learned.

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The What I Like About You and Hairspray star Tweeted the news to her fans. "I've unretired," she wrote on her Twitter page.

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Amanda took care of a little movie promotional business at the same time. She wants everyone to go see her new movie, Easy A, opening September 17.  She hasn't yet announced her next acting gig.