Can monsters on a US Pokemon Emerald be transferred to an AUS Diamond and Pearl via Pal Park?

I wanted to be sure before buying a US Emerald version (the game is no longer available here). I've heard some people claim that differing regions of the game can't be saved on my DS unit and that I won't be able to Pal Park monsters to my Australian Diamond and Pearl versions and some have claimed the opposite. Anyone know what's true and what isn't? Thanks in advance.|||in pokemon emerald the pokes are different and yes you can trade them over but go on a website called marriland.com and search the poke you want and usualy you can find it in poke diamond with the item that shows you where pokes are in the grass hope i helped