dunno if this is it, but i DID notice a temp directory in the languages directory.
i simply deleted it. seemed to me to NOT be needed and then i did the upgrade
i posted about it in a thread somewhere and am not sure if there was a reply as to why it was in there.
now, of course i only have upgraded sites with English..
but i'd think that you should try the upgrade without the directory..
if you need help, you can PM me info and i can look @ your site
