KATE Moss had a bust-up with rocker boyfriend Jamie Hince after she was grabbed by a man in a banana hammock thong at Simon Cowell‘s $1.6 million 50th birthday bash. The supermodel, who was partying hard at the champagne-soaked party near London on Saturday, was tackled by a burlesque performer flown in from New York’s The Box. A spy reports, “The man was singing Journey’s ‘Don’t Stop Believing’ and stripped down to a thong. He waded into the crowd and grabbed Kate, picked her up and started twirling her around. But as soon as he put her down, Jamie stormed over and began shouting at her.” Party organizer Lady Tina Green stepped in to calm things down, and the pair patched things up before leaving together at 4 a.m. Other guests included Ryan Seacrest, Randy Jackson, David Hasselhoff, Sharon Osbourne and Naomi Campbell. Reps for Moss, The Box and Cowell all refused to comment.