Beside of your problem with your mouse in X (according to your log), this is a config / startscript issue. I had similar problems with kdm. For me, it worked to 'apt-get remove --purge kdm' and then install it again with 'apt-get install kdm' - that did the job. Don't try to look for documentation and edit configs, this is not very pleasant in this case because of the several X startscripts playing together in some way. Joerg