I'm using sitecore 5.3 and need to be able to remove the extra query string parameters that sitecore inserts (item=%2faeuaoeu&user=extranet\Anonymous&site=thl) when redirecting to the 404 page specified in ItemNotFoundUrl.
In Sitecore 6 I can set
<setting name="RequestErrors.UseServerSideRedirect" value="true"/>
and it works but that setting doesn't exist in sitecore 5.3
I need it so I can fix this asp.net vulnerability
Edit: Sitecore's official response has been described in this article