:something => {:foo => 1, :bar => 2} in a GET request

rubyonrails-talk
1

This has been fixed for Rails 2.0. I also needed this to work, so I tried backporting the changes, but it's pretty tricky. So I just created a work-around function. You can get it on my blog at http://darwinweb.net/article/Nested_Hashes_In_Url_For_Parameters