Code:
function disableForm(theForm) {
  if (document.all || document.getElementById)
  {
    for (i = 0; i < theform.length; i++)
    {
      var tempobj = theform.elements[i];
      if (tempobj.type.toLowerCase() == "submit")
      {
        tempobj.disabled = true;
        tempobj.value = "Searching";
      }
    }
    return true;
  }
}