There are cases where it'd be nice to be able to set the protocol (for ssl) easily, when you don't have access to the X-FORWARDED-PROTO header, such as in Jamis' post Buckblog: Mongrel, SSL, and Apache 1.3 . The current behavior also means ssl_requirement chokes under Apache 1.3.
I wrote about it a little more, along with my simple work-around of overloading request.ssl? in a before_filter: http://www.timocracy.com/articles/2007/07/03/getting-ssl-and-redirect_to-working-without-custom-proxy-headers.
But, I was thinking it might be nice if redirect_to(string) honored default_url_options[:protocol], so that it could be handled consistently in configuration, rather than having to muck with protected methods of the request.
Would there be any interest if I submitted a small patch?