[gdm-list] automatic change default working directory after graphical login

[primorec <geda mail gmail com>]

short description of the problem:
I would like to automagically change the working directory from $HOME
to, for example, /proj/$USER after the $USER logs into the machine via
the graphical (GUI) login (aka gdm). So, when the $USER opens new
terminal, he/she should be in /proj/$USER and __not__ in $HOME
[side note: I am using tsch as my $SHELL]

oo: no, putting 'cd /proj/$USER' into .cshrc is _not_ the solution

oo: yes, putting 'cd /proj/$USER' into .login works if the user logs
into the machine using CLI login and then starts the desktop with
'startx' OR if he/she logs to the machine via ssh|telnet. It does not
work for gdm (aka graphical login)

oo: no, adding 'cd /proj/$USER' to the file Default or Xsession does
__not__ work.

/etc/gdm/PostLogin/Default
/etc/gdm/PreSession/Default
/etc/gdm/Xsession

oo: no, I do not want to change variable $HOME to point to /proj/$USER

oo: no, I do not want to modify /etc/passwd file

Simply put, I am out of ideas. Any hint, RTFM pointer or solution is
appreciated.

Igor