GREEN BAY -- Aaron Kampman still isn't talking, and Donald Driver isn't anywhere to be found because he wants his contract reworked.

Those were the two big news stories from the Green Bay Packers' first open-to-the-media organized team activity practice Thursday at the Don Hutson Center.

Kampman, the two-time Pro Bowl defensive end who is moving to left outside linebacker in the team's new 3-4 defense, participated in practice at his new position, but afterward, he declined to address reporters.

A team spokesman said that Kampman had "initially agreed to speak with the media, then ultimately decided not to make himself available." Kampman did the same thing at the annual FanFest in March.

Packers coach Mike McCarthy acknowledged that Kampman was initially reticent about the switch from the 4-3 defense to the 3-4, saying, "I think there's always hesitancy when you're asked to do something different. Aaron was very comfortable in the old scheme."

However, McCarthy maintained that he believes the switch will ultimately benefit Kampman, who is entering the final year of a four-year, $21 million contract.

"I don't want to be redundant but I think this defense is going to help Aaron Kampman," McCarthy said. "I think this is going to create more opportunity for him, the diversity of the scheme. First and second downs are clearly different for him. The sub packages, there's some multiplicity there that I think will also help him. I think he moves well in space. He's spent a lot of time with (outside linebackers coach) Kevin Greene. I know (defensive coordinator) Dom (Capers) and Kevin feel very good about where Aaron is today and he's only going to get better."

Asked about Kampman, linebacker A.J. Hawk said, "He's done a great job. Maybe the first day a couple of months ago in our IPWs, it was different seeing him stand up and drop into coverage and do stuff. But he's done a great job. I think he's enjoying it now. He's done some good stuff these last couple of days. I give him credit because that's a big transition going from D-end all the time to standing up and having to think a lot more and do different things. He's really transitioned well.

Meanwhile, two NFL sources said -- and a team source confirmed -- that Driver was absent because he wants the team to sweeten his contract. Driver, 34, has two years remaining on his contract, which calls for a $3.9 million base salary this season and a $4 million base salary in 2010. This is the fourth straight year that Driver has approached the team about reworking his deal, the team source said.

An email to Driver's agent, Jordan Woy, was not immediately returned. Attempts to reach Driver have so far been unsuccessful.

McCarthy wouldn't address the specifics of the absence of any of the three non-injured veterans -- Driver, cornerback Charles Woodson and safety Nick Collins -- but did acknowledge that "business" is involved.

"As far as the guys that are not here -- Donald Driver, Charles Woodson, Nick Collins -- no different than we've done in the past, I know everybody here understands that whether it's personal reasons, business reasons, whatever they are, I'm not going to discuss those," McCarthy said. "I know the fans respect that we don't do business in the media."

Collins, whose father, James Collins Sr., died of cancer at age 56 on Saturday, also is not in attendance, as expected. His absence, though, is related to his unhappiness with his contract, which has one year remaining on it.

Earlier this month, Collins' agent, David Butz, told the State Journal that even if Collins hadn't been dealing with his father's illness, he would not be participating in the offseason program.

“As always, family comes first and foremost with Nick, as it should,” Butz said at the time.  “But despite any other issues or concerns, Nick would not be attending the offseason program – regardless of any family matters.”