With Gilbert Arenas suspended for the rest of the season and Butler dealt, Jamison, who's been with Washington since 2004, is the only one of what was once the Wizards' Big Three remaining.
"We still have the trade deadline. There's still a lot of conversations going on," Ernie Grunfeld, Washington's president said on Tuesday.
The deadline is 3 p.m. ET on Thursday.
Grunfeld refused to speculate on a possible Jamison move. The 33-year-old Jamison, who's averaging 20.5 points, has been rumored to be coveted by the Cleveland Cavaliers. He did not speak with reporters after practice.
"We're still exploring things," Grunfeld said. "We want to see what this group does. If we don't make a move by Thursday, there's also the opportunity to make a move during the summer."
Washington received four players from the Mavericks -- forwards Josh Howard, Drew Gooden, center James Singleton and guard Quinton Ross. All except for Gooden practiced with the team; Gooden was said to be traveling to Washington on Tuesday night and scheduled to be available for Wednesday's game with Minnesota.
The Wizards did not address a media report that Gooden would negotiate a buyout of his contract.
Washington starts the second half of the season with a 17-33 record, ahead of only the sorry New Jersey Nets, who have a 4-48 mark, in the Eastern Conference.
"We had high expectations. Most people picked us to be one of the top four or five teams in the East and to win between 45 and 50 games, and that just didn't happen," Grunfeld said.
Howard, who was an All-Star in 2007, has been limited to 31 games this season due to a slow recovery from offseason left ankle surgery. He also had left wrist surgery. Howard is averaging 12.5 points this season.
"I'm coming here with a positive attitude, playing hard and trying to get us into the playoffs," Howard said. "We can make a strong push and get the eighth spot -- if not the seventh."
Howard leaves Dallas, where he made the playoffs in each of his six seasons, for a team that had lots of turmoil this season. Arenas and Javaris Crittenton both admitted to bringing a gun into the locker room after a dispute stemming from a card game on a team flight. Both were suspended for the balance of the season.
"The things that happened before I got here -- that was in the past. They handled it well," Howard said.
Wizards coach Flip Saunders, who has four trips to conference finals on his resume, isn't used to rebuilding teams. He said that it was still possible for his revamped team to make a playoff run.
"We'll know in the next couple of weeks," Saunders said. "How quickly the new players adapt will determine how we'll be."
Grunfeld, who's been forced to dismantle the team he's painstakingly built over the last 6½ seasons, is eager to see what he's left Saunders with.
"Anytime you make a change, it gives you a little bit of a rejuvenation," Grunfeld said.