Too many rtc interrupts

Hi folks, I've recently installed linux kernel 2.6.12 ( actually it was 2.6.12-1.1398 from RH Fedora Core 4). All seemed to be nice despite one thing - interrups number reported by vmstat was too much in comparision with ones on previous 2.6.11 kernel. To be precise it was in order of magnit

VM subsystem bug in 2.4.0 ?

and tryed to do the same, all passed ok! I think this is bug in kernel ( VM subsystem ) code. Informix allocate about to 50% of memory as LOCKED shared memory segments. I'm thinking the reason in this. Kernel wants, but can't to swap out locked shm's segments. Thank you. Sergey E