On my T42p, the BIOS settings for IRQs were factory set to 11. Changing those settings from 11 to 'auto' fixed some lockup issues I was having with the wireless interface after a resume from suspend-to-ram.
This is true and still accurate with FC 6, at least on my X22. By changing the BIOS settings for PCI IRQs from "11" to "Auto" I solved random lockups.
- View /proc/interrupts for conflicts on IRQ 11.
- Reboot to BIOS-Config-PCI and change all to "Auto.
- Save and Reboot.
S3 Suspend was already working for me.