Just to add my two cents...I was actually very surprised that this ever worked. When you connect to a shared folder, you are "mounting" the remote share onto /Volume/ folder on your local Mac. Espionage on the other hand works in a way that it mounts locally a disk image onto folder you picked as mointpoint.
Now, what you are trying to achieve is to access a local mount (the protected folder) through a remote mount (the shared folder), so no wonder it is freaking out :-)
I know this does not help you a lot and you will surely ask "but how come it worked so far", but obviously Apple did some slight changes in the AFP and SMB code which now you see the result of.
What I can offer you is to access the folder by accessing the disk image through the share and mounting it locally.
For this to work, you have to install Espionage on a local mac, share the folder in which the Espionage disk images are located (normally it is Library/Application Support/com.taoeffect3.Espionage/Data) and then import this disk image into the Local Espionage installation. Would that be interesting to you? If so, let me know and I will tell you how to do it.
Rgds
Zsolt