Problems receiving Hotmail mail when external MX servers are configured

[luigidelgado]

Hi. Im having this issue where people from Hotmail can't send mail to my Google Apps clients.
Finally found an explanation: Hotmail looks primary for A records not MX records (thank you Microsoft!). So they look for port 25 (which I have blocked) and dismiss MX servers. Google Apps or any other external email server will be ignored (has anyone noticed that before here?)

Some users may have external MX servers, some others may have them localy so I cant drop Hotmail servers from IP Tables.

Any ideas? How can I "force" Hotmail to look for MX servers instead to deliver the emails?

Thanks!