I think adding the ability to add specific countries to the Spam or Blocked filter would enhance the product greatly. I use Intermail PostOffice mail server on one machine, strictly for its Mailing List feature as it more robust than AMS's. However being an older program, it doesn't have RBL blocking capabilities. You have to manually add IP's to the blocked list. I was receiving about 14000 spams per hour from Taiwan which was clogging up the server. I acquired a list of all the IP blocks assigned to Taiwan and added them to the list. Now I get about 2-3000 spams per day, none of which come from Taiwan. I plan to add Korea to the list next. There are certain countries which are known for having a large amount of open relays and Spam activities. Allowing us to block these countries in their entirety from a list would be a great thing.
Granted, not everyone may want to block entire countries. However I do because none of my users have legitimate reasons for receiving mail from Taiwan or Korea and reducing Spam from these countries would be greatly appreciated by my clients. I would suggest adding the "option" for users to include entire countries to their individual spam filters, or allow us administrators to make it a global restriction on the server. Specific IP blocks could be added to the white list for cases where you'd require specific servers to get through. All it took me was a few hours to prepare a text file of Taiwan's IP blocks for me to block Taiwan from my other mail server. At the minimum, perhaps you can add a text box to AMS's Spam filter or Black List where we can copy and paste a bulk list of IP blocks that we wish to refuse mail from.
Thanks for your consideration.