i think i'm doing this right, and xfree86 2.0 with xdm seems to running
   fine. however, logins from xdm do not appear in response to finger and
   who requests, so i assume utmp isnt being modified properly.

Define `properly'.  xdm doesn't normally frob utmp unless you
specifically modify the scripts in /usr/X386/lib/X11/xdm to do it.
xterm sessions normally show up because xterm is setuid root and
diddles utmp.


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