Australian senator Chris Ellison, has said that a prisoner exchange deal between Australia and Indonesia, could be online in early 2007. Since Schapelle Corby was arrested a couple of years ago, and the likelihood of young Aussies spending a long amount of time in jail, became a possibility, the 2 governments have worked towards an agreement.
The plight of the Bali Nine is still up in the air, with 6 member currently on death row. That may change in future, allowing them to serve their sentence closer to their relatives. I did some reading up on extradition treaties and found that its a complicated business. Some countries sign solo treaties with one other country, others join a block of countries to sign an agreement. Certain local sticking points of often get in the way, for example Japan is willing to extradite foreign citizens, but not its own citizens. Othe countires have a problem, with the possibility of the death penalty. The prisoner exchange has its compications too, with the length of sentence / remissions / parole proceedure etc. having to agreed upon by both sides.