well brother... i'm here to say two things that may make your day. One is to seriously consider Thinking Sphinx. I've had a blog post that got wiped out regarding that post, as i used it for like 2 years (aaf and shared indexes). Thinking sphinx is more 'better'.
unless you can do one, then i assume you are forced to use aaf. i suggest it has to do with how you are starting/stopping the ferret server.
Here is what worked for me, as it is literally magic...
- stop the ferret server
- Restart passenger/mongrel
- start the ferret server
- do a search in your app (actually search for something and hit submit)
- Delete the
/index
directory, like all of it
- Do another search and it should work
Lame as it is, just remember that Thinking Sphinx is capable of doing what you want with shared indexes.