This port requireat least s version 1.41 of the Qt library.
There will be an error reported by configure, if only an earlier
version is found, but no automatic port dependency exists (i.e.
the x11-toolkits/qt141 port has to be manually built and installed).
There may still be a problem with a missing -lXext in the kdesupport
port. This will be taken care of during the next few days, if the
problem still exists ...
kwm - window manager
kfm - file manager
kdm - login manager (xdm replacement)
kcc - KDE config tool
kvt - xterm replacement
... and too many more to list here ...
I have not yet tested the functionality of kdm, but there seems
to be a problem with decoding the screenlock password, so it may
be wise to use KDE with xdm for now (or to use startkde, which
also shows what to add to your .xsession file, if you want to
stay with xdm).