function isEmailAddr(Email)
{
	var result = false
	var theStr = new String(Email)
	var index = theStr.indexOf("@");
	if (index > 0)
	{
		var pindex = theStr.indexOf(".",index);
		if ((pindex > index+1) && (theStr.length > pindex+1))
		result = true;
	}
	return result;
}

function valid_form()
{
	if (document.signup_form.SH_Request_Email.value == "")
	{
		alert("Please enter a value for the \"Email\" field.");
    	document.signup_form.SH_Request_Email.focus();
    	return false;
  	}
  	if (!isEmailAddr(document.signup_form.SH_Request_Email.value))
	{
		alert("Please enter a complete Email address in the form: yourname@yourdomain.com");
		document.signup_form.SH_Request_Email.focus();
		return false;
	}
	if (document.signup_form.SH_Request_Email.value.length < 5)
	{
		alert("Please enter at least 5 characters in the \"Email\" field.");
		document.signup_form.SH_Request_Email.focus();
		return false;
	}
}