<h:commandLink id="area1" onclick="dlg.show()">
...
</h:commandLink>

<ppctu:dialog onCloseUpdate="... here is all the component ids from the dialog content           ..."  modal="true" widgetVar="dlg">

function getFile(url) {
  if (window.XMLHttpRequest) {
    AJAX=new XMLHttpRequest();
  } else {
    AJAX=new ActiveXObject("Microsoft.XMLHTTP");
  }
  if (AJAX) {
     AJAX.open("GET", url, false); //notice the 'false' attribute
     AJAX.send(null);
     return AJAX.responseText;
  } else {
     return false;
  }
}