Stephanie Birkitt, the former personal assistant to David Letterman who appeared in numerous skits on The Late Show, has been identified as one of the women now believed to have been sexually involved with David Letterman. Birkitt, who lived with alleged blackmailer Robert "Joe" Halderman, was not, however, responsible for the extortion plot.

According to TMZ, it was Hadlerman who "was in possession of Birkitt's diary, correspondence and photos -- which he says incriminated Letterman." Despite rumors that Birkitt once worked at Tonight Show with Jay Leno, NBC h as confirmed that those allegations are false.

TMZ is saying that Letterman and Birkitt had a sexual relationship that did not extend beyond 2003.

Earlier this year, Letterman wed his girlfriend of 23 years, Regina Lasko, with whom the late night star has a young son, Harry.

More About