function checkform ( form )
{
  // see http://www.thesitewizard.com/archive/validation.shtml
  // for an explanation of this script and how to use it on your
  // own website

  // ** START **
  if (form.email.value == "") {
    alert( "Please enter your email address." );
    form.email.focus();
    return false ;
  }

  // VALIDATE EMAIL ADDRESS MORE
  if (!validEmail(form.email.value))
  {
	alert("Invalid email address")
	return false;
  }

function validEmail(email)
{
	invalidChars = " /:,;"
	
	if (email == "") 
	{ 
		return false
	}
	
	for (i=0; i<invalidChars.length;i++)
	{
		badChar = invalidChars.charAt(i)
		if (email.indexOf(badChar,0) > -1)
		{
			return false
		}
	}
	
	atPos = email.indexOf("@",1)
	if (atPos == -1)
	{
		return false
	}
	
	if (email.indexOf("@",atPos+1) != -1)
	{
		return false
	}
	
	periodPos = email.indexOf(".",atPos)
	if (periodPos == -1)
	{
		return false
	}
	
	if (periodPos+3 > email.length)
	{
		return false
	}
	
	return true
}
 
  // ** END **
  return true ;
}