The "spurious" IRQ messages are annoying when one is logged onto the system console at the tower. They are logged at a priority of "warning". They should have a lower priority, like debug, or info, unless the number/sec is above some threshold. Until that change is made, I'll disable them on the console, by setting the "-c 4" option in klogd, which then suppresses messages of warning and lower, which are numeric values 4-8. 3-0 are priorities from error to emerg.
That change was made to /etc/init.d/klogd on Oct 24, 16:45 UTC, and klogd restarted.
To see the spurious messages, do either of the following:
cat /proc/kmsg dmesg
cat /proc/kmsg removes the messages from the kernel message ring buffer as they are read.