That's a new check in the 2.2.19pre kernels (not part of the aa patchkit).
It means your timer chip didn't resetted itself to the timeout value (LATCH)
after triggering the irq and in turn it means you are losing system time (you
lose more time the the higher is the irq latency). I don't know the details of
the hardware bug though, maybe somebody else can give more details on it.
It doesn't look like a sw problem (previous kernel would malfunction silenty if
that would happen without such a new sanity check).
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