I've recently (actually, last month, but I had been a bit too busy
since then) come across a wee problem, in what I originally thought
was the VFAT code -- having `utf8' as one of the options, creating
UTF-8 file names on a VFAT partition mysteriously gains a couple of
(random) characters just after the UTF-8 escaped character: eg.
touch "fooCbar" where C is an UTF-8 escape sequence ends up creating
a file named "fooCRbar". (R being some random character.)

I eventually tracked it down to one line in fs/nls/nls_base.c -- the
UCS-2 (wchar_t) string pointer was being incremented too fast. After
consulting Ogawa Hirofumi-san on the subject, he mentioned that
include/linux/nls.h also needs to be changed for proper UTF-8
support in the NLS code.