function checkLogin(theForm)
{

  if (theForm.Username.value == "")
  {
    alert("Please enter a value for the \"Username\" field.");
    theForm.Username.focus();
    return (false);
  }

  if (theForm.Username.value.length < 3)
  {
    alert("Please enter at least 3 characters in the \"Username\" field.");
    theForm.Username.focus();
    return (false);
  }

  if (theForm.Username.value.length > 30)
  {
    alert("Please enter at most 30 characters in the \"Username\" field.");
    theForm.Username.focus();
    return (false);
  }

  if (theForm.Password.value == "")
  {
    alert("Please enter a value for the \"Password\" field.");
    theForm.Password.focus();
    return (false);
  }

  if (theForm.Password.value.length < 3)
  {
    alert("Please enter at least 3 characters in the \"Password\" field.");
    theForm.Password.focus();
    return (false);
  }

  if (theForm.Password.value.length > 30)
  {
    alert("Please enter at most 30 characters in the \"Password\" field.");
    theForm.Password.focus();
    return (false);
  }
  document.getElementById('Login').disabled=true;
  return (true);
}