Strange problem. We setup inittab to start X in the following way:
1:2345:respawn:/bin/su - joe "/usr/bin/startx"

All was working fine until we changed joe's shell from bash to tcsh and now at boot up we get:
userclientrc=/home/joe/.xinitrc: Command not found.
userserverrc=/home/joe/.xserverrc: Command not found.
sysclientrc=/usr/X11R6/lib/X11/xinit/xinitrc: Command not found.
sysserverrc=/usr/X11R6/lib/X11/xinit/xserverrc: Command not found.
defaultclient=/usr/X11R6/bin/xterm: Command not found.
defaultserver=/usr/X11R6/bin/X: Command not found.
defaultclientargs=: Command not found.
defaultserverargs=: Command not found.
clientargs=: Command not found.
serverargs=: Command not found.
userclientrc: Undefined variable.

If I startup as root in a bash shell and then execute "su - joe" and then execute startx it works fine. Although right after we su to joe we get:
Warning: no access to tty (Inappropriate ioctl for device).
Thus no job control in this shell.

What is causing this problem? I know the obvious joke here, I guy goes to his doctor and says it hurts when I do this. The doctor says don't do that. Any way it would be nice to start this user off in tcsh. Thanks for your time.

I would try changing line 1 in /usr/bin/startx

from : #!/bin/sh

to : #!/bin/bash