I'm afraid I won't be able to fix that bug just now - I'm flying off to Japan on hollidays for one week, and I doubt I'll be able to do any coding over there.
In the meantime, you can sort of fix it yourself, even though it's not entirely satisfactory:
- open the preferences, click on the misc tab, select 'use custom shell' and put in 'cmd /c'
- close muCommander, go and open your preferences.xml file (check this thread out for how to locate it: http://www.mucommander.com/forums/viewtopic.php?t=443
- locate the bit that says <encoding>UTF-16LE</encoding> and replace it by <encoding>windows-1252</encoding>
- save, close, restart muCommander
It should work fine, except for accentuated characters which are going to be a bit messed up.
That's obviously only a temporary fix, and I'll work on getting muCommander to use the system's encoding. It's surprisingly harder than it looks, but I think Maxence and I came up with something that might work.