Telkom and MTN have not signed a roaming agreement, although it can't be long before they do.

It was reported yesterday that a deal had been struck, which would start paving the way for Telkom to become the country's fourth cellular operator.
Howeer, Telkom has issued a statement saying that, although it is negotiating with the mobile operators, not agreements have been signed.
Telkom intends to become a cellular operator this year and this would necessitate roaming agreements with the other operators being in place.