Roth, Adam Carolla rumored to replace Stern.

Fans eager to hear a fresh episode of the Howard Stern Show following the cast’s two-week vacation got a rude awakening this morning.

No Stern.

Instead, someone purporting to be former Van Halen frontman David Lee Roth had taken over the syndicated radio show.

There was an ill-prepared Diamond Dave commenting on Hollywood news, playing guess-that-Diamond-Dave-tune, taking calls from irate listeners. One called him a “washed up rock star” who needed to go on Ritalin. Another begged for someone to say it was all a joke.

Between it all were clips of classic VH songs, Roth’s trademark scream and a Stern show effort to portray what radio could be like without him. At one point, the Roth impersonator expressed his joy with being back in the media spotlight, saying he was “bigger than the London bombings.”

After the show’s first commercial break, someone who identified himself as a Viacom exec explained that the company had chosen not to wait until Stern leaves the company for satellite radio in January 2006 to launch his replacement. The carefully orchestrated radio theater-of-the-mind reached a peak when the faux Roth – played to a T by Billy Mirra-- put a caller on the air. It was Stern, saying he received a phone call on vacation, informing him that he didn’t need to show up for work any more. Thanking "Roth" for putting him on the air, Stern berated Infinity for not allowing him to do a farewell show.

Shortly after 7:00 A.M., Stern was back behind the mic, copping to the prank and explaining to listeners that he wanted them to know what the show might be like under Roth, who has been named as a possible replacement. Adding fuel to the rumor, Stern said Infinity has hired Roth and Loveline co-host Adam Carolla to replace him.