It seems to me you've found a money making opportunity. If there's no good way to convert bitcoin to rand, perhaps you should be the guy to do it. Instead of mining, you could be collecting up all the bitcoins throughout SA in exchange for depreciating currency and a nominal transaction fee. With a little marketing you could be rich before Friday. If you didn't want to hold the coins, you could at least send them to Mt Gox and convert them into the currency of your choice.

Can't you set up a US dollar (or Euro) account in South Africa for receiving dollar transfers and do the currency conversion at the bank?