Missing action error not being caught

I keep getting a blank page containing only the following:

"There was a controller specfic error processing your request."

Though I have the following in my application.rb

def rescue_action_in_public(exception)         case exception         when UnknownAction, ActiveRecord::RecordNotFound then             render :controller => "application", :action => "error_404", :status => 404         else             render :text => "errors/unhandled", :status => 505         end     end

Well. A lot has happened since this error. It is gone now, but I am not sure what fixed it.

I think it was changing "UnknownAction" to "::ActionController::UnknownAction"

-Matt