Description:
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The u format char behaves inconsistent.

1. In output the it uses 6 digits. When used in date_create_from_format it recognizes only up to 5 digits (though microseconds would be 6). So date_create_from_format('m-d-Y H:i:s T', $dateTime->format('m-d-Y H:i:s T')); will generate an error.

2. Though DateTime does not support microseconds (or does it?) and should cut them off it behaves very strange when parsing a date with fractional seconds.

Reproduce code:
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$d = date_create_from_format("m-d-Y H:i:s.u T", "03-15-2005 12:22:29.00000 PST");
echo $d->format("m-d-Y H:i:s.u T");
$d = date_create_from_format("m-d-Y H:i:s.u T", "03-15-2005 12:22:29.00100 PST");
echo $d->format("m-d-Y H:i:s.u T");

Expected result:
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03-15-2005 12:22:29.00000 PST
03-15-2005 12:22:29.00000 PST

Actual result:
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03-15-2005 12:22:29.000000 PST
03-15-2005 12:22:29.100000000 PST