Howard Stern Fighting With Sirius

I guess things aren't so rosy between Howard and Sirius despite the recent renewal of his contract. "In a lawsuit filed Tuesday in New York, Stern, his agent Don Buchwald and Stern's production company, One Twelve Inc., claim Sirius failed to pay stock awards due in exchange for helping the satellite radio service exceed its subscriber growth targets." So one must wonder, is there more to this story. Contracts are never as clear cut as they are meant to be. Has Sirius found a loop hole to stop paying Howard stock or is something else amiss?