Fragment Caching

I'm using regular expressions in expire_fragment function. Using it this way appears to stat EVERY single file in the entire cache directory. I thought that it was only expiring fragments from the controller it was called from, this appears not to be the case. This of course leads to SIGNIFICANT performance issues once you get a sizable number of files in your cache directory and could potentially expire fragments from another controller that you would not want to without realizing it. From looking at the source from cache.rb it looks trivial to build a plugin to take a controller as an option and only stat files from that path. I'm a relative newbie however and just wanted to make sure I was using it right way and not missing some rails convention for specifying the path that the regular expression applies to. Any insight would be appreciated!

Cheers, Dallas