Last night, i download all the -current updates in Slackware's repository (besides the 2.6 kernel, since i'm find with the 18.104.22.168 kernel that i build). When i got home, i started by updating the NVidia driver first, since it will require the same GCC version that was being used to compile the kernel and i want to upgrade my GCC, so it's best to upgrade the NVidia driver first. After the installation is complete, i upgrade all packages in -current package (except for kernel 2.4 also, since i'm quite happy with 2.4.31 and 2.4.x kernel was only used for rescue mode when 2.6 kernel was having some problem).
When i rebooted my system, i got some strange error message, saying that MySQL has been started and in two seconds, it ended again. GDM also display some weird error messages saying that the /var/lib/gdm didn't existed. I had to restarted my system and log into textmode. I checked the directory and it was there. I hacked my system for a few hours trying to solve the MySQL and GDM problem and finally i got the solutions. Reinstall MySQL and GPM could solve the problem. I don't know why reinstalling GPM solve this problem, but it works as it is. Perhaps it's because the installation will set the permission again. It also works for MySQL.