How do i block a certain subfolder from being indexed?

It is a symlink to a folder that i use for other software, but zenphoto should not index it because it gets stuck in it (to many folders). I cant change the access on filesystem level because that would break my other software.

I have tried the unpublish option but this doesn't stop ZP from indexing the folder.

Is there another option in ZP?

Zenphoto is file system based so automatically indexing what is on the file system is the core feature and cannot be disabled.