Australia’s busiest Hollywood actress Melissa George celebrated her birthday (31) in L.A. on Aug.5, then whisked back home to Perth to visit with her parents before winging out to another film location later this month. It’s the Jan De Bont-directed actioner “Stopping Power” with John Cusack. Melissa was birthday-partied on her birthday by Nikki Haskell — designer shades for everyone — on every table. You recall Melissa and Nikki are prepping a biopic based on Nikki’s adventures in NYC in the ’70s. It took a little imagination to picture the transformation of the statuesque blonde from Down Under into the petite brunette hot Gothamite of the ’70s as the duo posed together for the party’s lensers. Melissa’s husband, the charming Chilean director Claudio Dabedwho, also delighted the birthday party guests. Nikki took a break from party-hosting for the rest of this week as she recovers from benign tumor surgery (by a plastic surgeon) for a condition she admits having had for three-four years. Nikki’s now A-OK, she happily reports.