[Zope] mc-ftp crashes zope

hello, when i connect with the gnu-midnight-commander (mc) to my zope-ftp-port (8021), zope crashes if i submit a wrong login. this happens on linux (zope 2.4.3, mc 4.5.51) and freebsd (zope 2.4.1, mc 4.5.54), so i think it must be a problem of zope... ftping with a normal client works well... what's wrong with zope and midnight-commander? thanx4hlp maik.