Ashton Kutcher has poked fun at David Letterman's 'fatwa' during an appearance on the veteran TV host's chat show.
A contributor to a jihadist website last week posted a threat of violence against David because he had joked about al-Qaida leaders on a previous show.
Ashton came on stage for Wednesday's taping wearing a helmet and a bulletproof vest printed with the phrase, 'Not Dave'.
During the show, David asked Ashton if his bow-tie was bullet-proof. The actor replied that "you can't be too careful" sitting next to a man facing a threat.
Ashton joined CBS comedy Two And A Half Men after Charlie Sheen was fired. He and David predicted success for the revamped sitcom.