In Karmic Koala 09.10, the powers that be removed the UI to switch on XDMCP. This enables one to log-in remotely to your workstation / computer from another Linux box. This comes in very, very handy but its also a bit non-secure. (Which is probably why the people in charge of Gnome / Ubuntu stripped it out). But is still there if you want to use it.
The following instructions are adapted from this blog entry. Its mostly the same, I've just removed some of the original authors slightly more rambling (no offense intended) introduction. Hit the "Read More" Button to see the instructions / tutorial.
gksudo cp /usr/share/doc/gdm/examples/custom.conf /etc/gdm/
gksudo gedit /etc/gdm/custom.conf
# GDM configuration storage[xdmcp]Enable=true[chooser][security][debug]
gksudo restart gdm
I'm the slightly rambling original author (no offence taken :-) ). I just thought I'd recommend a different post than the one you linked to, which has more details, and which I've just updated to also recommend adding "DisplaysPerHost=2" to the GDM config file as well:
Sorry about that... I was in a hurry at work trying to set this up... :D That's certainly an in-depth look at Remote Desktop options...!
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