function Form_Validate_EmailFormat(source, clientside_arguments)
{
    var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i
    
    if (filter.test(clientside_arguments.Value))
        clientside_arguments.IsValid = true;
    else
        clientside_arguments.IsValid = false;
}