During a stern cross-examination, Bianca Singh, Schabir Shaik's former personal assistant, conceded that she had been mistaken about the date when a vital set of cellphone calls took place.

Singh spent yesterday afternoon in the Durban High Court being cross-examined by Francois van Zyl SC, appearing for Shaik, who is standing trial on charges of corruption and fraud. Van Zyl was due to resume cross-examination of Singh this morning.

Singh told the court that in 1998 she had been in Shaik's office when he took a call on his mobile from his brother Chippy, who was then head of arms acquisition in the defence department and a person playing a key role in the multi-billion rand arms procurement programme.

Shaik had told Chippy "not to worry" and had immediately dialled another number and said, "Hello my brother, hello JZ" - Singh said he was clearly talking to deputy president Jacob Zuma.

According to Singh, Shaik had then continued: "Chippy's under pressure and we really need your help to land this deal."

Later, Singh said she had apparently made a mistake and was no longer certain whether the calls had taken place some time between mid-1988 and March 1999, as she had originally said, or in October 2000 around about the time that the Parliamentary Standing Committee on Public Accounts was deliberating on the arms deal.

Van Zyl also put it to her that Shaik never called Zuma "JZ" but only "my brother" or "chief".

Singh said she had on a number of occasions heard Shaik call Zuma "JZ".

She also did not withdraw her allegation that the conversations, as remembered by her, had taken place.

Singh also testified before lunch yesterday that in November 2000 she had accompanied Shaik to a meeting in Mauritius with Alain Thetard and another man, both from arms dealer Thomson.

She said Shaik had taken her in keeping with his promise that, having been promoted from receptionist to personal assistant, she would play a greater role in the company.

He had, however, warned her that in her new role she would need to be at his "beck and call" and had explained to her that that was what his relationship with various "ministers" was.

"He said he has to carry a jar of Vaseline because he gets f****d all the time but that's okay because he gets what he wants and they get what they want."

With acknowledgement to Jeremy Gordin and the Cape Argus.