xdm login infinite loop

[whollygoat@letterboxes.org]

I can't login in graphically.  My password is
accepted, the screen goes blank and flickers like
when it is starting up a session, then just
returns me to the login display.

I'm using xfce and xdm on a thinkpad i series
laptop.

I know my password is being accepted because
the screen behaviour is different for a wrong
password.

/var/log/Xorg.0.log, /var/log/xdm.log and /var/log/auth.log
are all being touched without any input being added 
to the files.  In fact, xdm.log and Xorg.0.log are
both zero length files (nothing has been written
to them.

The only messages are in .xsession-errors, but
googling seems to indicate that they are innocuous:

----- .xsession-errors excerpt ------
** (x-session-manager:2398): WARNING **: xfsm-shutdown-helper.c:134:
Failed to contact HAL: Rejected send message, 3 matched rules;
type="method_call", sender=":1.6" (uid=1000 pid=2398
comm="x-session-manager ")
interface="org.freedesktop.Hal.Device.SystemPowerManagement"
member="ThisMethodMustNotExistInHal" error name="(unset)"
requested_reply=0 destination="org.freedesktop.Hal" (uid=0 pid=2175
comm="/usr/sbin/hald "))
** Message: xfsm-shutdown-helper.c:215: HAL not available or does not
permit to shutdown/reboot the computer, trying sudo fallback instead.
xfce4-tips: Fatal IO error 11 (Resource temporarily unavailable) on X
server :0.0.
xfce-mcs-manager: Fatal IO error 11 (Resource temporarily unavailable)
on X server :0.0.
--------- end excerpt -------------

I vaguely recall someone experiencing something
similar, but my googling didn't turn up anything

Thanks,

-- 
  
  whollygoat@letterboxes.org

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