Katy Perry's rumored on-again boyfriend John Mayer is reportedly filing a lawsuit against an ex-bouncer who implicated the singer in a drug deal. In other news, the "Your Body is a Wonderland" hitmaker will reportedly join The Grateful Dead reunion tour.

According to the report, the whole case stemmed from the suit filed by Leonard Taylor against Barry Mullineaux, owner of NY bars Greenhouse and Wip.

The lawsuit alleged that Mullineaux forced him to purchase cocaine for the bar's celebrity guests including Uma Thurman, Mark Wahlberg and John Mayer.

"Mayer was among the names mentioned in the lawsuit, and a spokesperson for the musician has now spoken out to vehemently deny the claims and threaten legal action against Taylor," the report said.

A rep for Katy Perry's rumored on-again boyfriend John Mayer, however, told Page Six that the charge is "completely untrue. It's a flat-out lie. I'm certain Mr. Mayer's attorneys will become involved."

Mullineaux, for his part, told Page Six that Leonard Taylor has been stalking him for years.

"Every time he shows up he says, give me $10, give me $20, give a me a job or I'm doing this, for three years stalking me and threatening me. Nothing he says has any truth or value to it. It's all lies," he said.

Meanwhile, John Mayer will reportedly join The Grateful Dead reunion this fall, Billboard said.

"According to insiders, the trek is due to kick off in October, with the Grammy-winning singer and guitarist having already begun to jam in a rehearsal-like setting with select members of the group, chief among them Weir," the report said.

Katy Perry's rumored on-again boyfriend, John Mayer, is reportedly "ecstatic about the prospect."

However, a rep for The Grateful Dead told Billboard that it's too early right now to be talking about John Mayer joining the planned reunion.