One of the products that I've gotten a chance to work with, here at 3Sharp, has been PostPath. Billed as a Microsoft Exchange alternative, it is a set of Open Source packages and management tools that emulate an Exchange server in an Active Directory environment. I am not doing a lot with this product at the moment, but when I was setting it up, I ran into a couple of problems. While I was able to work around them, I thought that I would talk about the two major problems that I ran into.