Mike Chiappetta at NBC Sports has the details:

BJ Penn has sent a formal request to the Nevada State Athletic Commission, asking them to investigate Georges St. Pierre and the actions of his cornerman during their UFC 94 bout last Saturday night.

The letter was sent by Penn's lawyer Raffi Nahabedian to Nevada state athletic commission executive director Keith Kizer. In the correspondence, which was given by the commission to NBCSports.com, Nahabedian states that the letter is not a formal complaint, but asks the commission to ensure that St. Pierre and his cornermen are "properly dealt with."

...

In Nahabedian's letter to the commission, he wrote, "Simply put, by lubricating GSP's body, a highly slippery surface was created that completely neutralized an innocent participant's abilities and strategy to the advantage of GSP." It goes on to add, "More importantly, by neutralizing Mr. Penn's Brazilian jiu-jitsu abilities through the use of illegal and improper means, Mr. Penn was subjected to a life-threatening and career-ending environment; an environment that the Commission was armed to protect against."

Nahabedian claims that Penn's camp told the commission prior to the bout of the possibility of St. Pierre greasing. During the fight, commission members did towel down St. Pierre, but Penn's letter makes it clear the UFC welterweight champion was still too slippery.

NOTE: This is NOT a formal complaint, only a letter asking the commission to look into matters. Let the games begin.

The only mind-blowing aspect to the story is this response from Executive Director of the NSAC Keith Kizer:

Kizer, however, told NBCSports.com that while the written regulation doesn't outlaw greasing the body, fighters at MMA events are verbally told by both the commission and the promoter that it is not allowed.

Asked whether the rules should be amended to include no greasing the body, Kizer said, "Not necessarily, but it wouldn't hurt. The reason for rules is to give notice as to what's illegal, and they have notice of that."

It wouldn't hurt? Given the volcanic levels of uproar this matter has caused, ironing out the rules to make them clear and then taking more active measures to enforce them seems all but paramount. I certainly respect Kizer and understand he takes his position very seriously, but the necessity of adjusting the legal language is far beyond an idea that "wouldn't hurt".

And as Michael Rome pointed out to me, what are the implications if Jackson were to lose his cornerman license? Far reaching, to put it mildly. In terms of offering cogent advice between rounds his ability is virtually second to none. His fighters would miss him greatly. Granted, the majority of the attention is on Phil Nurse, but one must consider all possibilities at this stage.