WEBrick can't find new controllers

I’m sure this is something simple in my configuration.

Simple for you, I hope.

I’m trying to learn Rails via online tutorials. I run into a problem
when I create a new controller ($ script/generate controller MyTest).
When I try to view the empty controller in Mozilla, instead of an
“index not found” I get “/mytest not found”. I can see the /public/
index.html just fine on the default port 3000. I’m simpling adding /
mytest to the end of the URL.

I’m running WEBrick 1.3.1 on Ruby 1.8.5 in Fedora Core 5.