Former Vodacom group CEO Alan Knott-Craig contradicted himself under questioning over who invented the “Please call me” service while testifying in the high court in Johannesburg on Tuesday, according to a newspaper report.

According to Wednesday’s Business Report, Knott-Craig contradicted himself while being questioned by Cedric Puckrin, who is representing Nkosana “Kenneth” Makete, a former Vodacom employee who claims he came up with the concept and is seeking recompense from the operator.

In his autobiography, Second is Nothing, Knott-Craig claimed he developed the service by chance after observing two security guards trying to communicate in Vodacom’s executive office block. One sent a missed called to the other to attract his attention.

However, in court on Tuesday, Knott-Craig claimed Philip Geissler, then Vodacom’s executive for product development, invented the idea, the newspaper said.

But by the end of the day, Puckrin had succeeded in getting Knott-Craig to admit that Makate had come up with the idea, it added.

The “Please call me” service allows prepaid customers without airtime to send a message requesting a callback to another subscriber. These messages were commercialised by selling portions of them to advertisers.

Knott-Craig, while giving evidence in the morning, told Vodacom’s counsel, Fanie Cilliers, that Makate had simply presented an idea with no technical solution. He said the merit was in the technical solution.

The former Vodacom boss could not explain why Geissler agreed in an e-mail in 2009 to corroborate the version published in Knott-Craig book.