Description:
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there is something wrong with date format. I'm using DataTime object in Propel script and this date ('0000-00-00 00:00:00 ') is given from database. when i try use it DataTime object it display "-0001-11-30 00:00:00"

Reproduce code:
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<?php
$dt = new DateTime( '0000-00-00 00:00:00' );
var_dump( $dt->format( 'Y-m-d H:i:s' ) );
?>

Expected result:
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string(20) "0000-00-00 00:00:00"

Actual result:
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string(20) "-0001-11-30 00:00:00"