session manager and user environment in XFCE4

[Agi Subagio]

> What about creating a script and calling it - with the "sleep" command
> in it...keep in mind that if you're starting X from a console, .xinitrc
> is what is called - and if you're starting from GDM/KDM/XDM, the
> .xsession is called...so having the same data in both files (or just
> nail down the one that you're actually using) should help...

Do you have any example for this?
I have the same content in .xinitrc and .xsession file, but still won't
work... :(
I'm starting with graphical (init 5) setting.

> Are these variables something you might want to include in the
> /etc/profile so that they're system wide, or is this strictly per user?

This is only for some user.

I want to use linux for some user with a little knowledge of using computer.
We have a custom application that run on linux.
Everytime he turn on his machine, the system will automatically login with
his username and password.
After that, our custom application will come up immediately without his
interuption.
I can do that with GNOME/KDE, but those desktop env is heavier and longer to
load than XFCE4.

So.. what should I do next?