London, Aug 23 - Kimberly Conrad, ex-wife of Playboy boss Hugh Hefner, is suing the porn mogul after he reportedly went back on their pre-nuptial agreement.

They split in 1998, but never formally divorced - their relationship remained amicable with Conrad residing near Hefner's Playboy Mansion in Beverly Hills. But now Hefner has gone against their amended pre-nuptial deal by trying to sell Conrad's home and giving her nine months to move out, reports imdb.com.

Conrad filed a suit against Hefner at LA Superior Court and also claims he owes her more than $5 million.

Conrad married Hefner in 1989 and has two sons - Marston and Cooper - with the octogenerian.