Exchange 2003 Relay Issue

Hi,

Is it me. Or does Exchange 2003 still allows relay by default. Microsoft claims that its relay is closed but when i check using third party testers on the web, it still allows relay. I been through all the knowledge base article on closing the relay, but still when you check with third party tools, it still allows it. Using the same third party tools in exchange 5.5, it doesn’t allow relay. I really don’t want to be blacklisted so what’s the best option at this point?