I'm using Zeph's 10.5.2 on AMD, and it's working almost flawlessly. The thing is, after a few hours, os keyboard shortcuts stop responding. Application shortcuts work ok (copy, paste, whatever) but anything system-wise don't (exposé, spaces, dashboard, grab, etc).

I'm using the latest AppleSMBios.kext, Mac OS X 10.5.2 (9C7010) Kernel 9.2.0. Keyboard and Mouse are PS/2 (well, keyboard is actually USB but I'm using an adapter).

Any ideas on why this may be happening?

Hm, i wondered why the Screenshot hotkey for screen parts (Shift+Alt+4) and the fullscreen snapshot (Shift+Alt+3) made the photo 'snap' but there were no picture icons on the desktop... until I noticed that I was using the wrong keyboard :-P

No, no idea. What if you use other keys for the system things? i remove all functions of the f-keys up to F12 cause other programs could use them. The dashboard is F13 (print on Win keyb), Exposé (All Windows) in the lower right corner, Spaces in the lower left corner and 'Show Desktop' on the middle mouse button.

Well, I tried changing them and it seems to work. But I don't really like the available keys (Shift, Control, etc).
It seems some application is blocking some shortcuts, because it worked with any key excepting for F1...F12. The wierd thing is Alt+Tab isn't working either. I'm going insane!!!

Nobody knows why may this be happening? It's getting really annoying and I don't know what else to do.

You can try the program Onyx. It is a program which cleans up the Mac and so on. maybe it solves the problem.

Thanks naquaada, just tried that but it didn't solve my problem :(

Have you tried booting in safe mode (option -x)

Thanks for your suggestion naquaada, I'll try that next weekend. In case I leave Leo running for 24 hours in safe mode and shortcuts still work, what could be the problem?