Britney Spears' first husband is behind bars in Los Angeles, serving a 10-day sentence for a DUI offense.

Jason Alexander, who was married to Spears for just 55 hours at the beginning of 2004, was sentenced to jail time after failing to complete a court ordered alcohol rehabilitation program for a 2006 DUI arrest, according Star magazine.

Ironically, the prison term comes a day after Alexander's ex-wife celebrated her 27th birthday and released her comeback album, Circus, which in on course to top the charts in the U.S. next week.

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(This news article provided by World Entertainment News Network)