Shar Jackson (left) and Britney Spears Photo by: Jon Kopaloff / FilmMagic; INF
Shar Jackson Gives Britney Spears a Bum Rap | Britney Spears, Shar Jackson
Shar Jackson isn't a musical superstar just yet, but she is ready to take on Britney Spears, the ex-wife of her own ex-boyfriend, Kevin Federline.

Performing as Shar J on MTV's Celebrity Rap Superstar, Jackson gave a spirited performance on Thursday night of "Let It Blow," a rap she wrote herself.

With verse after verse extolling her many virtues, Jackson looked directly into the camera and rapped, "They should have had me open up at the VMAs!" – a sentiment that elicited screams of delight from the crowd.

Jackson, who has two children – Kori, 5, and Kaleb, 3 – with Federline, all but branded Spears a homewrecker in 2004, saying the pop princess had stolen her boyfriend of four years.

She has since maintained that she bears no ill will – toward Federline, at least. Jackson has even publicly praised his parenting skills.

On Celebrity Rap Superstar, the field has been narrowed to just the two finalists: Jackson and Kendra Wilkinson, one of Hugh Hefner's three live-in girlfriends on the E! reality series The Girls Next Door.

Following last night's show, viewers have until 11 p.m. Friday to vote by phone or text message for a winner.

Jackson has dabbled in music before, as part of the R&B group MPULZ, which contributed a track to the Princess Diaries soundtrack. She is better known as an actress, having played Niecy Jackson on the 1996-2001 UPN show Moesha.
This week's cover

On Newsstands Now!

JOSH & FERGIE: ROCKED BY SCANDAL

Did he cheat with a stripper?

Married less than a year, the couple denies an Atlanta woman’s claims that she and Josh had a fling
Note that this week’s cover of PEOPLE may differ regionally

Save $1.00 off this week's issue. Click here for coupon