I have found several postings asking about suspend problems on IBM
thinkpads, but no answers so far. Here is what I have so far:

Using APM with ACPI and CPUfreq disabled: Suspend works, but only if
running on battery. When running on AC, I get what sound like PCMCIA
failure beeps (brief high low), the display goes dark, but the system
keeps on running and hitting any key brings be right back (at least
usually, using earlier versions of 2.6 circa .2, the system would
sometimes lock up after restoring the screen, at which point, sometimes
C-A-Del or Alt-sysreq-B would work, and sometimes not.)

FWIW: there were no problems with suspend under any 2.4 kernels. 

.config is attached. Let me know if anything else would help.

-- 
Vincent C. Jones                 VCJones@NetworkingUnlimited.com