function validateEmail(addr)
{
  if (addr == '')
  {
    alert('email address is mandatory');
    return false;
  }
  var invalidChars = '\/\'\\ ";:?!()[]\{\}^|';
  for (i=0; i<invalidChars.length; i++)
  {
    if (addr.indexOf(invalidChars.charAt(i),0) > -1)
    {
      alert('email address contains invalid characters');
      return false;
    }
  }
  for (i=0; i<addr.length; i++)
  {
    if (addr.charCodeAt(i)>127)
    {
      alert("email address contains non ascii characters.");
      return false;
    }
  }

  var atPos = addr.indexOf('@',0);
  if (atPos == -1)
  {
    alert('email address must contain an @');
    return false;
  }
  if (atPos == 0)
  {
    alert('email address must not start with @');
    return false;
  }
  if (addr.indexOf('@', atPos + 1) > - 1)
  {
    alert('email address must contain only one @');
    return false;
  }
  if (addr.indexOf('.', atPos) == -1)
  {
    alert('email address must contain a period in the domain name');
    return false;
  }
  if (addr.indexOf('@.',0) != -1)
  {
    alert('period must not immediately follow @ in email address');
    return false;
  }
  if (addr.indexOf('.@',0) != -1)
  {
    alert('period must not immediately precede @ in email address');
    return false;
  }
  if (addr.indexOf('..',0) != -1)
  {
    alert('two periods must not be adjacent in email address');
    return false;
  }
  var suffix = addr.substring(addr.lastIndexOf('.')+1);
  if (suffix.length != 2 && suffix != 'com' && suffix != 'net' && suffix != 'org' && suffix != 'edu' && suffix != 'int' && suffix != 'mil' && suffix != 'gov' & suffix != 'arpa' && suffix != 'biz' && suffix != 'aero' && suffix != 'name' && suffix != 'coop' && suffix != 'info' && suffix != 'pro' && suffix != 'museum')
  {
    alert('invalid primary domain in email address');
    return false;
  }
  return true;
}