True, but I won't be able to afford it until I get a real job x) And eBay never seems to have the Japanese version :<
Also, does anyone know exactly why the old cast was replaced? o.o
It's a long story, and depending on who you talk to it goes differently, but essentially:
Pokémon USA own the rights to the Pokémon anime, but for the first eight seasons they employed a company called 4Kids Entertainment to do the dubbing from Japanese to English. This is not uncommon - 4Kids do quite a few English-dubbed anime. The voice actors (VAs) who 4Kids used to do the Pokémon series are mostly exclusively contracted to them, so they can't work as dub voices for any other companies.
Pokémon USA's contract with 4Kids ran out at the end of Pokémon: Advanced Battle. However, instead of renewing the contract, P-USA declared themselves dissatisfied with 4Kids and decided they would now dub the episodes themselves, using a sound-alike cast that cost them far less money. Whether this is the reason they decided to do it or not is up for debate and nobody will likely find out for a looong time, but the upshot of it is that P-USA found new VAs. However, they needed to test them against the public audience, so they requested the feature special Pokémon: Mastermind of Mirage Pokémon, under the premise that it was to celebrate the tenth anniversary of Pokémon's introduction in the USA.
Before and especially after the Mirage special aired, P-USA received various complaints about the VA change. With a few exceptions, all the 4Kids dubbers were now unable to work on the new series, but many viewers were also dissatisfied with the voices in the Mirage special. P-USA took this on board and improved the voices, ready for Pokémon: Battle Frontier.
Therefore, since 4Kids and their exclusive VAs now no longer work on Pokémon due to their contract with Pokémon USA being up, the episodes are now dubbed by a new cast which is employed by Pokémon USA for far less money.
Hope that answers your question! Heh.