The above code is what I'd recommend using, as it's simple enough that the use of modules isn't really needed.. Then again I'm not a module-nazi:) One caveat about this code though: The value returned to $month in the call to localtime is 0 based, i.e. 0..11. I'm not sure if this might contrast the format of the $birth_month that is being passed in.. if so, just change the appropriate line to read

$age-- unless sprintf("%02d%02d", $month+1, $day)
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