I say again, filetypes with mime decides the type depending on the
actual _data_, what it contains. File extension is basicly just a cheap
trick to `know' it's type even before the file has been opened, and can
therefor be easily faked - or mistaken.

You are fully right.

But I seem to be the only one that likes the idea with mime types, and
everyone is fighting against me on the subject... `resistance is futile'
- at least it seems to be :(

IMHO, mime types is not the solution. Something like mime-magic is probably better but has its limit. How to handle files with unknown content but known extension and how to handle new file format or "rare" ones (who knows PES format ?).

Eric