<?php

    // assume we are in London
    date_default_timezone_set('Europe/London');

    // assume that today is March 25, 2012
    $date1 = new DateTime("2012-03-25 01:00:00");
    $date2 = new DateTime("2012-03-25 02:00:00");

    // and...
    if ($date1 == $date2) {
        echo "WTF?!? Equal???";
    }