rootnl asks: "Recently I decided to upgrade my email server with better spam detection and decided to use the SORBS blacklist. It is a very aggressive blacklist and could be deemed quite effective. However, I discovered two totally legal servers currently being blocked by their Spam 'o Matic service: a Google Gmail server (18.104.22.168), and another server belonging to an ISP called Orange (22.214.171.124). Now, normally one would think these providers would probably get themselves de-listed, but the process provided revolves around donating money. As I just happen to have a friend that is using the said ISP, I have to seriously reconsider using SORBS. What is your experience with SORBS? If you have alternatives, what would you suggest as a better blacklist service?"