(Photo credit: Courtesy B.Toccafondi )

Happy early birthday to Charlize Theron!

The Oscar winner, who turns 38 on Wednesday, celebrated her big day a few days early - in Italy. On Sunday night, Theron stopped into Antica Pesa in Rome with four friends around 9 p.m. (It's nice to have friends in high places - owner Francesco Panella, the actress's pal, opened the eatery just for her.)

"She was in great spirits, looking beautiful and admiring the Roman sky," a source tells ABC News of the actress, who wore a chic black dress for the occasion and dined on the dimly-lit patio.

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For dinner, the group sipped red wine and nibbled on mozzarella and prosciutto before digging into pasta dishes - cacio e pepe, with cheese and pepper, and all'amatriciana, with pork and tomato.

"They were very relaxed," the source said, adding that everyone sang happy birthday after dinner and celebrated with birthday cake. After Theron blew out her candles, she took a photo with Panella [above] and was "super gracious" to the staff as she said good night.