Description:
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Either manual page (http://www.php.net/manual/en/dateinterval.format.php) or DateInterval is broken somehow.

I have understood that charected 'i' means minutes, not like 'm' (like in example). This will produce an error and is hard to handle simple ways is 'm' is used BOTH months and minutes.

Test script:
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# Works
$date = new \DateTime();
$date->add(new \DateInterval('P2Y1M4DT6H8M'));

# Not working
$date = new \DateTime();
$date->add(new \DateInterval('P2Y1M4DT6H8I'));

Expected result:
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Returning the current day plus interval.

Actual result:
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Error