iMessage not activating on iPhone 5

Hi - any idea how to get iMessage activated on Telkom mobile with the Telkom mobile number?

Its a prepaid number.

I have put the sim in, switched phone on, went to activate iMessage and FaceTime, tells me that my carrier may charge to activate it.

I click ok and it keeps on saying 'waiting for activation'

I need it to activate on the Telkom Mobile number but it just keeps hanging with that message saying waiting for activation.

Tried in 3 x different iPhones - same error/activation message? Tried a Vodacom sim and Cell C sim in same iPhone and they both register iMessage perfectly.

Telkom store in Clearwater sends me to iStore for help. iStore Clearwater sends me back to Telkom Mobile store for help.

Tried the Telkom mobile call centre and got a '...sorry, we don't know how to solve that...maybe there is a network problem. We'll get technical to call you...'

6 x calls to the call centre in 2 weeks and still nothing...

WTF?

Fail to understand how Telkom can sell the iPhone but one of its core features does not work on its network...?

Now what...?