Update on Friday 2010-09-24: A kind person named Milo in Vodashop Hatfield, initially also baffled by my dilemma, managed to determine that I needed to phone 100 from the Vodacom SIM card in order to “activate” it even though I was receiving SMS on it already at that point. Now, on day 5, I have two active SIM cards on the same number and seem to be receiving SMS messages and calls from all networks with the call terminating on either on of the two phones. Sigh.
It took me more than one visit to the Vodacom service centre in Menlyn to discover what the exact procedure was (RICA documents, completely fresh SIM card from another shop, officially weekdays 8am to 5pm only but in practice 10am to 3pm). On Monday afternoon, I made a special trip during office hours and it appeared that everything went well. Late in the evening, the number became unstable on VM and I could no longer receive calls from Telkom but I expected something like this to happen. On Tuesday I put the Vodacom SIM card into my phone but I could not receive calls either. It is now Thursday and I can still receive calls and SMS messages from Cell C on my VM SIM card and can make calls from VM (showing the correct number as CLI) but I am receiving SMS messages (but not calls) from other networks on the Vodacom SIM card (!?) which I cannot recharge so I have no idea whether I can use it to call or not.
Needless to say, I despair – of the workability of porting in SA, of the ability of these networks to make anything work (are they just Telkoms with wings, after all?) and welcome any suggestions. Good luck, Kenya!