How do I add mouse devices after debian upgrade?

I had a problem after doing etch upgrade to xorg that /dev/psaux and /dev/input/mouse
are not there. X was running (the old xserver) before upgrade.
How do I add those devices? or fix it?
This was an install from Knoppix 3 years ago and now have done many apt-get upgrades since then.

Somebody recommended typing:
dpkg-reconfigure xserver-xorg
It asks me a bunch of questions.
I then type:
startx 2> junkfile
I see junkfile says: xf86OpenSerial: Cannot open /dev/psaux
ls /dev/ps*
no such file or directory
Thanks
JF

you did the etch upgrade to xorg to knoppix?

3 years ago, installed knoppix. Upgraded every 6 months, so
it is really a debian system now. It's a i386

Did the big upgrade to etch 2 months ago. After that,
no X windows or KDE due to no /dev/psaux.

Solved:
Had to check the links in /vmlinuz and /initrd
and saw the kernel was not upgraded.
Had to use _ to remove configuration files for a
kernel I had previously tried to upgrade to
or the upgrade would not work to that kernel.
(Note: that seems like a bug in dpkg, apt-get, aptitude, etc)

add psmsouse to /etc/modules


Then dpkg-reconfigure xserver-xorg.

I posted more complete details in linux.debian.user
usenet group (didn't show up in the email list at debian.org website?).