In short, she can demand her the contract be cancelled as the goods are defective. The CPA is quite clear about this:
Section 56:
(2) Within six months after the delivery of any goods to a consumer, the consumer
may return the goods to the supplier, without penalty and at the supplier’s risk and
expense, if the goods fail to satisfy the requirements and standards contemplated in
section 55, and the supplier must, at the direction of the consumer, either—
(a) repair or replace the failed, unsafe or defective goods; or
(b) refund to the consumer the price paid by the consumer, for the goods.
Which would allow her to sign another contract for the overpriced, underspeced piece of crap she wants.
She's also got all sorts of other CPA rights due to the product not being clearly marketed and so on.
Vodacon will deny this and fight tooth and nail to continue illegally ripping of consumers, and the National Consumer Commissioner is so busy fighting scum like Vodacon on other fronts that you'll be lucky to have the case resolved before the end of 2012.
Sorry.