Well, usually it is a permission problem. Try to trash yourself the folder you want to protect with Espionage...I'm not saying you delete it, just put it into the trash. If you are asked to authenticate, then the permissions are wrong. As Espionage does not have the option to ask you to authenticate, it just reports that it cannot trash it....
There is an option to ignore the permissions on the volume, select the volume, then get info on it and in lower part of the window you will see the option....
Or, you can simply create a new folder, try to trash it, if it does not ask you to authenticate, then it is only that old folder which has the problem, just copy all your files into this new folder and then Espionage should be able to trash it with no problem...
Let me know how it went,
Rgds
Zsolt