Yes, POPFile is compatible with Lotus Notes. Please read the Howtos section for more information on this. Unfortunately due to the design of Exchange, POPFile does not support it natively at this time. There is however an extension program called Outclass (formerly SpamFree for POPFile) that will allow POPFile and Exchange to work together. Outclass will be incorporated into POPFile as an official extension in a future version of POPFile. Read this discussion for more on how to configure Outclass.