function emailvalid(obj)
{	
	email = obj.value;
	if (email.length == 0)
		return true;
	else if (email == "none")
		return true;
	else if (email.length < 6)
		return false;
	else if (email.indexOf("@") == -1)
		return false;
	else if (email.indexOf(".") == -1)
		return false;
	else if (email.lastIndexOf(".") < email.indexOf("@"))
		return false;
	else if (email.indexOf(" ") >= 0 || email.indexOf("[") >= 0 || email.indexOf("]") >= 0 || email.indexOf("{") >= 0 ||
			 email.indexOf("}") >= 0 || email.indexOf(":") >= 0 || email.indexOf(";") >= 0 || email.indexOf("<") >= 0 || 
			 email.indexOf(">") >= 0 || email.indexOf("?") >= 0 || email.indexOf("/") >= 0 || email.indexOf("\\") >= 0 || 
			 email.indexOf(",") >= 0)
	{
		return false;
	}
	else
		return true;	
}