function openWindow(link) // inspired by porneL - http://pornel.net/pups/
{
  try
  {
    var new_window = window.open(link, '_blank');
    if(new_window) return false;
  }
  catch(e){}
  return true;
}

function checkRequiredFields(form_id, alert_text)
{
  ok = true;
  fields = document.getElementsByTagName('input');
  for(var i in fields) if(fields[i].id && fields[i].className.match('required'))
  {
    if(fields[i].parentNode.parentNode.id==form_id && (!fields[i].value || (fields[i].type=='checkbox' && !fields[i].checked)))
    {
      ok = false;
    }
  }
  fields = document.getElementsByTagName('textarea');
  for(var i in fields) if(fields[i].id && fields[i].className.match('required'))
  {
    if(fields[i].parentNode.parentNode.id==form_id && !fields[i].value) ok = false;
  }
  if(ok)
  {
    //document.getElementById('submit_'+form_id).disabled = 'disabled';
    return true;
  }
  alert(alert_text);
  return false;
}