Thanks for wishing me luck
I did it! I'm posting this 11PM Philippine time. Too sleepy now.
I've been carefully studying every kernel updates available in -current and I have tested all of them and I know what worked and what not. This is what I did so far:
The first release of kernel-huge-smp-2.6.33_smp-i686-1.txz worked for me.
I installed the kernel 2.6.33.1. Copied the config of 2.6.33 to /usr/src/2.6.33.1/.config and run
make oldconfig
make bzImage
Go to source/k/kernel-huge-smp and run the slackbuild
Install the 2.6.33.1-smp module package from slackware/a packages.
Run the slackbuild for kernel modules smp
Then install the two. Fix the rc.modules symlink and reboot.
It boots and X works out of the box (same as 2.6.33).
After learning so, I copied to packages to my main slackware and installed them.
Thanks all, marking this solved.