Because of a procedural requirement of Australian law, the Commissioner has been joined in Samsung's invalidity case against Apple in the Australian Federal Court proceedings. Samsung is not making any allegations of wrong-doing against the Commissioner and it is most unlikely that the Commissioner will take any active role in the proceedings. It is therefore inaccurate to state that Samsung has "sued" the Australian Commissioner of Patents.
Samsung is simply complying with Australian procedural requirements so it can make all possible invalidity arguments against Apple's dubious patents. Samsung's invalidity case against Apple is not new and has been in progress since Apple first commenced proceedings against Samsung in Australia last year. Samsung's claim against Apple always has been that Apple's patents should be revoked, and the new procedural aspect of the claim does not change that in any way.