The "Application Error (Rails)" page is returned with status=200, it should be 500. It works correctly with mongrel.
I tried this, the my founding is interesting. I made some error in a controler code intentionally, so rails will produce a 500 Error page. When I run it in development mode, both mongrel and litespeed return 500 page, however, when I switch to production mode, rails return a page with 200, for both mongrel and litespeed, seems the old controler code without the error was used. It is a rails issue I think.