<form action="{URL->ACTION}" method="post" id="phorum_listform">
  {POST_VARS}
  <input type="hidden" name="action" value="list" />
  <input type="hidden" name="folder_id" value="{FOLDER_ID}" />
  {IF FOLDER_IS_INCOMING}
    {INCLUDE "pm_list_incoming"}
  {ELSE}
    {INCLUDE "pm_list_outgoing"}
  {/IF}
</form>
