hmm i don't know but messing with a host-file gives me the shivers. ok, it's cool to have an idisk-icon and such stuff... but i think it's not worth the risk. i prefer to use the connect to server-thingy or some app to connect to a webdav server.
gmx is great for copying data between different 'mediacenter'-accounts. if you can' make up a german address, use the german white pages for it (www.dasoertliche.de). pick a common name like schulze, schultze, meier, maier, müller,... enter a big city in germany and thats it. but please don't subscribe to something else than freemail. borrow the people's names but don't make them be pissed of
if you need some more info check the msj-site for more thoughts about gmx.