Can't expire cached pages

For some reason I can not expire a cached page. I have created a sweeper file and I know that the proper methods are being called. I have also tried just moving the expire_page call into the controller code, but it still doesn't work.

The main page is cached with the following to create an index.html file in the public dir: class PublicController < ...    caches_page :index

   def index       @blog_posts = Blog.find(:all, :limit => 10)    end    ... end

The following is what I have in the Admin::BlogPostController class

class Admin::BlogPostController < ...    cache_sweeper :blog_post_sweeper, :only => [:create, :update, :destroy]    ... end

And here is the sweeper: class BlogPostSweeper < ...    observe BlogPost

   def after_save       expire_cache :controller => "public", :action => "index"    end

end

As I mentioned earlier, I know that it is calling the sweeper method, but fails to delete the cached file.

Any ideas?

Thanks