Using a "non-supported" window manager

I'm attempting to remaster a Knoppix disk and use a window manager that's not in the "supported" windows manager list, i.e. one that isn't listed in the case statement in knoppix-autoconfig. If I try to enter something other than what's in that list, I get a message that says that window manager is unsupported and it's using twm instead. What script sets the window manager after knoppix-autoconfig sets the $DESKTOP variable? Do I need to modify this script or can I simply set up a .Xsession file somewhere on the disk? Thanks everyone for your help.

Matt

This was posted someplace before, anyway, I use fvwm, which is not around. So I apt-getted fvwm (using the remastering techniques) and then I changed /etc/sysconfig/desktop to read "wmmaker" and the script /cdrom/KNOPPIX/etc/X11/xsession.d/45xsession to read
"exec fvwm2" at line 512, where he starts wmmaker. That way I got fvwm and everything worked.
If I did "startx /usr/bin/fvwm" from the commandline using "2" I also got fvwm but you could not invoke mozilla from it. Nobody ever answered my query as to why not.
Also I am not using Knoppix's ways to find the best screen size. It is better to use "XFree86 -configure" in knoppix.sh and then use that XF86Config-4 config file

Hope this helps.

Hugo.

Thanks, Hugo. That did the trick.