To anybody who can help me troubleshoot why I can't login with KDM:

Here is an strace debug log (warning: large file if not on broadband):

http://humanreadable.nfshost.com/trinity/build_logs/kdm-trinity.log.gz

Slackware uses shadow passwords and does not include or support PAM. Therefore I built kdebase with the following:

-DWITH_SHADOW=ON
-DWITH_PAM=OFF

Thanks!

Darrell