Strolling hand-in-hand along the cobbled streets of Positano, on Italy’s Amalfi Coast, Cameron Diaz and Benji Madden turned every head they passed last month. But it wasn’t just the star-wattage that had locals coughing into their cappuccinos — the unlikely couple’s predilection for PDA also caused ripples along the Italian coast.

“Going on appearances alone, people can’t help but stare, as they look completely mismatched,” a friend of the actress admitted to The New York Post.

Indeed, the heavily inked 35-year-old rocker, whose romantic history includes Paris Hilton and Holly Madison, couldn’t be further from the 41-year-old actress’ usual type — which the friend describes as “clean-cut but with a bad-boy edge.”

Nonetheless, Diaz’s pals say that she might be willing to relinquish her status as one of Tinseltown’s most committed bachelorettes. The actress — who, in a recent interview, stated, “I don’t know if anyone is really naturally monogamous” — is seriously considering a walk up the aisle.

“Benji has pretty much moved into her house in Beverly Hills, and they’ve talked marriage,” her friend reveals. “None of us would be surprised if she called us and said: ‘Guess what? I’m Mrs. Madden!’ ”