Caught in the Act

Denise Richards & Richie Sambora Back Together for Friend's B-Day Bash

11/10/2011 at 06:00 AM EST

They're back on! Denise Richards and Richie Sambora celebrated a friend's birthday at the newly opened Rosa Mexicano in West Hollywood. The on-again couple arrived on the later side – after dinner was served – but they were in festive spirits for the bash, which was held in the restaurant's private dining room. Guests including Megan Fox and husband Brian Austin Green shared a round of the restaurant's famous frozen pomegranate margaritas. When it was time to go, Greene and Richards slipped out the back door to avoid the paparazzi. – Liza Hamm

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