Swat/SwatDate.php
public function setDate($year, $month, $day)
    {
        if (!checkdate($month, $day, $year)) {
            return false;
        }

        return parent::setDate($year, $month, $day);
    }
public function setDate($year, $month, $day)
    {
        if (!checkdate($month, $day, $year)) {
            return false;
        }

        return parent::setDate($year, $month, $day);
    }
public function setDate ( $ year , $ month , $ day ) { if ( ! checkdate ( $ month , $ day , $ year ) ) { return false ; } return parent :: setDate ( $ year , $ month , $ day ) ; }
Sets the date fields for this date

This differs from PHP's DateTime in that it returns false if the
parameters are not a valid date (i.e. February 31st).

@param integer $year the year.
@param integer $month the month.
@param integer $day the day.

@return mixed either this object on success, or false if the resulting
date is not a valid date.
Sets the date fields for this date