$zones = _system_zonelist();
      $form['timezone'] = array(
        '#type' => 'select',
        '#title' => t('Select your timezone'),
        '#default_value' => strlen($_POST['timezone']) ? $_POST['timezone'] : variable_get('date_default_timezone', 0),
        '#options' => $zones,
	'#weight'=>1
      );
    	$form['submit'] =array(
	'#type'=>'submit',
	'#value'=>t('Submit'),
	'#weight'=>5
	);

    print '<div id="timezonelist">'.drupal_render_form('timezone',$form).'</div>';