Jason Segel Tapes Michelle Williams Pics To Phone (PHOTOS)

When Jason Segel appeared on "The Tonight Show" Friday, he and Jay Leno discussed the decision to show his derriere in his forthcoming flick "The Five-Year Engagement." But perhaps the most revealing moment came after the 32-year-old actor returned home from the taping, when Segel's phone -- adorned with photo-booth pictures of new girlfriend Michelle Williams and the words "I love you" -- was caught on camera.

The bicoastal couple reportedly met through Williams' longtime pal Busy Philipps, who co-starred with Segel on "Freaks and Geeks," and have been spotted dining together in both Brooklyn and Los Angeles.

It's likely that Segel's sweet sentiment is mutual. "She hasn't been this happy in a long time," a source close to Williams, 31, told Us Weekly in March.

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