Running v5.0.13 - open source on Ubuntu 8.04. Following the guide on this site adjusted the percentages for Spam reject and deletion to block out more spam - it is working satisfactorily as less spam is ending up in the inbox & junk folder, however, there are a couple sites that are now being deleted that I would like to receive without opening the whole thing back up. Haven't been able to find anything with regards to creating a "whitelist". Is this possible and could someone point me in the right direction on how to do it?

Thanks