- date_create_from_format: documentation ( source)
- str_replace: documentation ( source)
- trim: documentation ( source)
<?php
// format: 08:25:50 Feb 20, 2014 PST
$payment_date = "08:25:50 Feb 20, 2014 PST";
$payment_date = trim(str_replace('PST', '', $payment_date));
$date_time = date_create_from_format('H:i:s M d# Y', $payment_date, new DateTimeZone('PST'));
if($date_time)
echo $date_time->format('U');
else
echo 'got fucked!';
?>