File::Tail does some math with time intervals in an attempt to predict how long it shoudl sleep before the next line of data will be available to be read. It seems from your error message that under some circumstances, the calculation can results in a negative number.

You could try modifying line 529 of File::Tail thus:

    sleep($object->interval > 0 ? $object->interval : 1 );
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where 1 is some arbitrary number of milliseconds (or seconds if Time::HiRes is not available), used as a default when the math goes wrong.

If that fixes your problem you could suggest it to the module author.