Ms. Campbell had been subpoenaed to testify about whether Mr. Taylor had sent her a gift of rough diamonds after the dinner. Prosecutors hope to show that Mr. Taylor lied under oath when he said that he never had any diamonds and did not trade any for weapons to support the bloody rampage by rebels in Sierra Leone during the country's civil war.

Ms. Campbell said she had been at a dinner with Mr. Mandela, Mr. Taylor and others at the presidential guest house in Pretoria, and had then retired to her room there. After she fell asleep, there was a knock on the door and two men presented her with a pouch. One of them said, "a gift for you," Ms. Campbell said.

The men did not introduce themselves or say who the gift was from, she said, and she went back to sleep without opening it. "I was extremely tired and I wasn't sure who they were," she said.