Right, so we all know that Optus decided to charge international call rates for some local numbers, to try to claw back some of the money they're losing as customers choose cheaper options to call home. A more sensible option would be to provide reasonable rates to existing customers - or set up such a VOIP service yourself, and let customers choose between the cheaper lower-quality VOIP service, or paying more for a "premium" connection - and maybe even snagging some customers from other carriers. That woud be hard though - so instead, lets just slug prepaid customers with additional fees to access the VOIP services, and pray that not too many of them port their service to a different provider.
But that's just stupidity. This is outright theft:
The most recent legal case, decided on November 27, also forced Optus to concede it had stolen 100 numbers from a tiny telecommunications carrier in Vanuatu and then allowed a pair of its pornographer partners, Global Internet Billing in Britain and MDC in Europe, to use the stolen numbers for their business.
Optus then kept the proceeds of these calls, money which would have normally been payable to the Vanuatu carrier.
 Of course, the difference would probably be entirely in the marketing and not in the implementation of the service, but that's nothing new.