JOHANNESBURG, South Africa - A woman accused of abusing teenagers at Oprah Winfrey's school for girls was acquitted of the charges yesterday, and Winfrey said she was "profoundly disappointed" by the trial's outcome.

Prosecutors had accused former school matron Tiny Virginia Makopo of trying to kiss and fondle girls at the school soon after it opened in 2007 outside Johannesburg.

Makopo also had been accused of assaulting one of the teens, as well as a fellow supervisor.

Mthunzi Mhaga, a spokesman for South Africa's National Prosecuting Authority, said yesterday that Makopo had been acquitted of the charges and that prosecutors wouldn't appeal.

Winfrey had called the allegations crushing, given her own stated history of childhood sexual abuse, and promised an overhaul of the school.

The lavish $40 million Oprah Winfrey Leadership Academy for Girls, which opened in January 2007, aims to give girls from deprived backgrounds a quality education in a country where schools are struggling to overcome the legacy of apartheid.

In March, Winfrey had settled a defamation lawsuit filed in Philadelphia by the school's former headmistress, Nomvuyo Mzamane, who alleged that Winfrey had defamed her in remarks made in the wake of the sex-abuse scandal at the school.

Mzamane alleged that she had never been told of any sexual abuse. However, Winfrey's attorneys said in a March pretrial memo that Mzamane had failed to discipline Makopo despite her history of run-ins with students and fellow staffers.