The lineup for the all-star [artist id="1102"]Michael Jackson[/artist] tribute concert slated for September 26 in Vienna, Austria, has gotten a bit less glittery. Just a day after [news id="1620905"]Jermaine Jackson announced[/news] the initial list of performers for the event he is coordinating to honor his late brother, representatives for two of the biggest contemporary names on the roster, [artist id="854"]Mary J. Blige[/artist] and [artist id="1961441"]Chris Brown[/artist], have denied that the artists will be involved in the event.

A few hours after Jackson announced the performers on Tuesday, a spokesperson for Brown told MTV News that the singer never committed to performing at the show. According to The Associated Press, the concert's promoter said a Los Angeles judge was scheduled to rule on Wednesday over whether Brown, 20, could travel to the show. Brown was recently sentenced to five years of probation and 180 days of community labor after pleading guilty to a felony charge of assault for beating his then-girlfriend Rihanna in February. He would need permission to leave the country for the gig.

A court spokesperson told the AP that no motion had been filed with the judge handling Brown's case requesting permission to travel overseas for the show, and an unnamed person with knowledge of the singer's situation said no such request would be filed on his behalf.

"Chris Brown is working out some situations, but he definitely expressed to us that he wants to be here, and it's just up to what he's going through with his court case right now, but he's definitely going to work that out and be here," Jermaine Jackson said at a press conference in London on Wednesday.

While the official Web site for the event still lists Brown and Blige on a roster that also includes Akon, Natalie Cole, 1970s disco icons Sister Sledge, Germany-based boy band US5 and actress Angela Bassett, a publicist for Blige has also denied that she will be taking part in the show. Though MTV News could not reach Blige's spokespeople for comment, an unnamed publicist told the AP that the singer has other commitments at a Gucci-sponsored concert in Milan, Italy, that day and will not be able to attend.

Further muddying the waters, a spokesperson for Cole told the AP that the singer has been in discussions with organizers, but that she may have a conflict and is not 100 percent confirmed. Reuters reported that during Wednesday's press conference Jackson said that while Blige did have a previous obligation, she was planning to fly in after her Milan performance and sing during the second half of the Jackson tribute. He also said that Stevie Wonder, R. Kelly and Maroon 5 would likely perform at the show, alongside a number of unnamed acts from India and the Middle East.