Jackson, a two-time Pro Bowler, has expressed discontent with his contract on his Twitter feed.
He will earn $565,000 in base salary this season, the last of his four-year rookie deal, and there is a sense he will not report until a new agreement is reached.
Quarterback Michael Vick, in his first interview with the media after the lockout ended earlier this week in Philadelphia, spoke about Jackson's status, laying the framework for a possible holdout by the receiver.
"DeSean just has some things to think about," Vick said at the time, "and some decisions to make that only himself can make."
Coach Andy Reid did not seem concerned over Jackson's status during his first news conference Wednesday, and ran through his Thursday morning practice as a walkthrough. It was not open to the media or public.
Quarterback Kevin Kolb was not on hand, either. The Eagles are expected to trade him to the Arizona Cardinals before week's end.
Jackson is coming off a season in which he caught 47 passes for 1,056 yards and six touchdowns as the Eagles went 10-6 and won the NFC East.
"I'm just being realistic about the situation," Vick said. "It's all in what DeSean wants."