Can't select KDE

[David Christopher Mccallum <ummccal1@cc.umanitoba.ca>]

I'm using Debian Sarge, and recently installed the nvidia proprietary
drivers and kernel 2.6.8-1-686  A day later, when I started up my machine,
I got a Gnome desktop session.  I logged out, selected a KDE session,
logged back in, but got Gnome again. I seem to be stuck with Gnome for the
forseable future...

Could this be a result of installing the kernel or the nvidia driver?  How
would I go about getting KDE running again?

I have gdm, an MSI GeForce FX5200, the "nvidia" driver, and I was previously
running kernel 2.4.27-1-386.

Thanks in advance,
Dave