Jennifer Lopez, Diddy Had Awkward Reunion at Oscars Bash

Credit: Gregg DeGuire/FilmMagic (2)

Jennifer Lopez's skimpy Zuhair Murad dress wasn't the only dramatic element of her Oscar Sunday.

After her scene-stealing turn onstage (and in front of a billion TV viewers), the singer-actress, 42, changed into another revealing Murad number (an ombre red sequin number) for Vanity Fair's star-packed after party.

Her date for the bash was Casper Smart, her 24-year-old backup dancer beau of several months. Upon her arrival at the shindig, however, Lopez encountered a more well-known man from her past: Diddy!

According to an observer, Lopez made a bee-line for her ex, whom she dated from 1999 to 2001, shortly after arriving. Although Lopez seemed "friendly" during their chat, she was overheard apologizing for not returning his calls and text. "It was weird," the observer adds.

Lopez, who famously dated Ben Affleck after splitting with the hip-hop mogul then known as Puff Daddy (real name: Sean Combs), 42, has been friendly with another ex: Marc Anthony. She and her husband of seven years (they shared twins Emme and Max, 3) announced their split last July but remain colleagues on their reality show Q'Viva!