If you are having a problem getting your wordpress 404 page to show up when using lighttpd you need to add the following to your lighttpd config file to tell it where to get 404 responses from:

[code lang=”ini”]
server.error-handler-404 = “/index.php?error=404”
[/code]

This assumes that your blog starts at the root directory.

[tags]wordpress, lighthttpd, lighty[/tags]