Hello.

I have noticed mbcs codecs sometimes generates broken
string. I'm using Windows(Japanese) so mbcs is mapped
to cp932 (close to shift_jis)

When I run the attached script "a.zip", the entry
"Error 00007"'s message becomes broken like attached
file "b.txt".

I think this happens because the string passed to
PyUnicode_DecodeMBCS() sometimes terminates with
leading byte, and MultiByteToWideChar() counts it for
size of result string.buffer size.

I hope attached patch "mbcs.patch" may fix the problem.
It would be nice if this bug will be fixed in 2.4.3...
Thank you.