CELEBRITY BIRTHDAYS (4/5/11): Krista Allen - 40  She's been on "Baywatch Hawaii", the naughty "Emmanuelle" and it's nine sequels, and on "Smallville" as the teacher who was so hot it set off Clark Kent's heat vision, but tabloid readers know her as George Clooney's one time girlfriend ...

Their on-and-off long-running romance began in 2002 and lasted close to two years, till Allen broke it off in March 2004. They rekindled things in 2006, and again in 2008. She just can't quit you, George! But who can?

--PHARRELL - 38   Producer-slash-singer-slash-musician ...

--Paula Cole - 43  Biggest hits: "Where Have All the Cowboys Gone" and "I Don't Want to Wait", which was used as the main theme song for "Dawson's Creek"