Oprah to defend defamation charges in Phila.

A federal judge has dismissed Oprah Winfrey's request to throw out a defamation suit filed against her by the former headmistress of her academy for girls in South Africa.

The judge ordered the trial to begin March 29 at U.S. District Court in Philadelphia.

The former headmistress, Lerato Nomvuyo Mzamane, originally filed suit in Sept. 2008 over comments Winfrey made after a sex-abuse scandal erupted at the Oprah Winfrey Leadership Academy for Girls near Johannesburg.

Mzamane, a former administrator at Germantown Friends School, worked at the academy from January to Oct. 2007.

A dorm matron at the school, Virginia "Tiny" Makopo, was charged in Oct. 2007 with sexually abusing six girls ages 13 to 15.

News of the charges "devastated" Winfrey, who was herself sexually abused as a child.

The suit, originally filed in Philadelphia Common Pleas Court, contends that during a news conference Winfrey suggested that Mzamane was not trustworthy and tried to cover up the allegations of abuse.

"I trusted her. When I appointed her, I thought she was passionate about the children of Africa . . . [b]ut I've been disappointed," Winfrey said, according to the suit.

The superstar talk-show host said academy officials hid facts and told students to "put on happy faces" when she visited.

"I feel that the girls were placed in an atmosphere where they were taught to be fearful and they were taught to literally be silenced," Winfrey said during the Nov. 5, 2007 news conference. "And so when you remove the systems and put in a different kind of leadership, all that will change."

Winfrey fired all the academy's dorm parents and did not renew Mzamane's $150,000-a-year contract when it expired at the end of 2007.

Responding to the decision, Winfrey's Houston-based attorney, Chip Babcock, said "Oprah and Harpo [Winfrey's production company] await the opportunity to present the case in court.

Mzamane's attorney, Timothy McGowan, was similarly curt.

"We await the trial," McGowan said.

Winfrey opened the private boarding school in 2007, making good on a promise to former South African President Nelson Mandela that she would contribute $10 million to establish a school for needy girls in a country where fewer than half complete grammar school. She later established a foundation to support the project.

About $30 million later, the Oprah Winfrey Leadership Academy for Girls opened in Jan. 2007 with a gala and ceremonies that drew Mandela and celebrities including filmmaker Spike Lee and singer Tina Turner.