I understand that and wish I had an answer for you that would resolve your issue, unfortunately I do not. I too purchased Mac OS X 10.6 Server to run for the same reasons, albeit different apps, and in the end I decided to purchase apps as necessary that would run under OS X 10.8.x and not depend on having to use a Virtual Machine at least for some apps that I otherwise would have. For personal use I still require the use of virtualization but more for Windows based apps that I haven't yet replaced with Mac apps due to either cost and or unavailability. One example of a WinApp that took me a long time to let go of, for personal use, was Microsoft Outlook however after using a Mac for over 7 years I finally with the purchase of my latest early 2013 Mac now use native OS X 10.8 Apps for what I used Microsoft Outlook for.
So unless someone from VMware jumps in to help you with your Eudora issue, which may really not be a VMware issue per se, it may never get resolved. So at some point just be open to switching to something different that doesn't require the use of virtualization.