Jessica SimpsonJessica SimpsonJessica Simpson's dad is not happy.

Because someone has been saying unsavoury things about his daughter.

Joe Simpson, who is also Jessica's manager, has said he wants to "beat the crap" out of Jackass star Bam Margera, for saying he once slept with Jessica.

Bam appeared on Howard Stern's radio show last week, and said the actress/ singer took him back to her parents' home in LA one night in April 2005, when she was still married to Nick Lachey.

He said: "We were just drinking margaritas and stuff, and you know, from there..."

The Jackass: Number Two star also told publication Us Weekly: "It was when her parents were away and Nick was away. It's not a secret."

Bam MargeraBam MargeraJessica's dad is furious and has made no bones about what he'd like to do to Bam.

He said: "As a father, I want to go beat the crap out of people who say things like this.

"It really hurts to hear people say things like this about my daughter."