Indy 10 SMTP server seems to have issues with Postfix

Hi,
I setup a quick SMTP server using indy 10 and it works great when I send
from outlook express or Thunderbird,however when I setup Postfix to
route certain domains to my Indy SMTP server it(Indy) just totally dies
(connection gets dropped and a AV pops up).

Is there something I am missing when recieving relays from another SMTP
server?  Postfix is the most standards based SMTP server i know of so I
don't think it's that.

Thanks,