>//This timezone uses a posix time zone string definition to create a time zone</span>
    time_zone_ptr phx_tz(new posix_time_zone(<span class="string">"MST-07:00:00"</span>));

    <span class="comment">//local departure time in phoenix is 11 pm on April 2 2005 
    // Note that New York changes to daylight savings on Apr 3 at 2 am)</span>
    local_date_time phx_departure(date(<span class="number">2005</span>, Apr, <span class="number">2</span>), hours(<span class="number">23</span>), phx_tz, 
          