Jason Mraz has told Tristan Prettyman "I'm Yours," RadarOnline.com is happy to report.  The couple became engaged Thursday.

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The pop star announced the good news on his Twitter page.  "SHE SAID YES.  For once, I am speechless," he Tweeted.

Tristan, a singer/songwriter, was even more enthused.  "Holy Crap! Man of my dreams!!!" she Tweeted back.  "For the rest of my life!!!"

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Amid all the year-end break-ups in Hollywood, the Mraz engagement is great news for the holidays.  Congrats!

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