Experts tried for hours and failed, but the soothing words of Winnie Madikizela-Mandela took just a few minutes to defuse a five-hour hostage drama.

She managed to convince a seemingly irrational student who had taken Wits University's administrator hostage at knifepoint to free the frightened woman.

He then handed himself over to police.

Apparently enraged that he could not continue with his studies, Thapelo Moselenyana, 22, confronted the dean of students in her office.

"There was an argument and he followed her into the adjacent office, which belongs to Mrs Glenda Lane. He tried to hold the dean by force, but she managed to get away, and he turned his attention to Mrs Lane," Wits registrar Dr Derek Swemmer said.

Lane administers the university's rollover loan scheme. Her office is situated on the ground floor of Senate House on the East Campus.

Moselenyana initially demanded three phone calls: one to the university's executive director of finance - to whom he later refused to speak - one to The Star newspaper and the third to Minister of Education Kader Asmal's office.

The Star was contacted by Moselenyana, who asked for a journalist to be sent out. He also made contact with Asmal's office.

The angry student made use of an available phone line in the office to call 702 Talk Radio twice, and also forced Lane to call Asmal's office and appeal to him to come and rescue her by talking to him.

Resident life officer Robert Sharman was involved in the initial negotiations with Moselenyana, but the discussion was then taken over by hostage negotiators from the police, while the Special Task Force came in to take control of the situation.

Moselenyana was kept under surveillance the entire time by task force members who monitored him through a hole in the office door as well as an opening in a window blind.

"At one stage we saw the hostage was struggling to breathe. So we got hold of an asthma pump and passed it through the hole, and he actually gave it to her," said Superintendent Chris Wilken, police spokesperson for Johannesburg.

Negotiations continued for hours, with Wits staff conceding only to review his case while Moselenyana demanded to speak to outsiders.

Attempts were made by Congress of South African Students representatives to speak to him, as well as by his mentor, MBA student Thabo Tofile, but to no avail.

Asmal, who was in a cabinet meeting in Pretoria, cleared his diary and agreed to speak to Moselenyana.

"I spoke to him for half an hour, and it was a very important conversation that will remain between the two of us," Asmal said. He failed to convince Moselenyana to give himself up.

Acting vice-chancellor Professor Loyisa Nongxa also spoke to Moselenyana, and then Madikizela-Mandela took over.

"She told him to hand the hostage to her and then give himself up. He did exactly that. He handed Mrs Lane over to Mrs Madikizela-Mandela and then allowed the police to arrest him," Nongxa said.

The student was taken to Hillbrow police cells.

Wilken said he would face charges of kidnapping, attempted murder, intimidation and assault.

The docket will be forwarded to the Director of Public Prosecutions for a decision.

According to Swemmer, Moselenyana entered the university armed with a kitchen knife late on Wednesday morning. He then forced his way past the secretary to the dean of students, into Lane's office.

Moselenyana enrolled for a BA in 1999, and completed his first year. He then decided to change to law and registered for an undergraduate BA LLB, but failed. In 2001 he enrolled for a second-year BA, but failed, and repeated the course in 2002.

Explaining the background, Swemmer said, "I cannot comment on his performance last year, but he is in breach of his contract with us. He undertook to pay his fees by the end of last February.

"The amount (more than R10 000) has been outstanding for 12 months and he doesn't qualify for a rollover."

This was why he had not been allowed to re-register.