Help with RESTful named url options

I've found quite a few posts on the subject, but no satisfactory
answers. Maybe Rails just doesn't support this yet.

How do I create a url with a named RESTful route that also has

I want to write this:

link_to_remote "Show Details", {:url => item_url(@item, :details =>
1), :method => :get}

And get this:

<a href="#" onclick="new Ajax.Request('http://localhost/items/1?
detail=1', {asynchronous:true, evalScripts:true, method:'get'});
return false;">Show Detail</a>

Instead I get:

You have a nil object when you didn't expect it!
The error occurred while evaluating nil.to_sym

active_support/core_ext/hash/keys.rb:27:in `symbolize_keys'
base.rb:518:in `inject'
active_support/core_ext/hash/keys.rb:26:in `symbolize_keys'
helpers/url_helper.rb:21:in `url_for'
(eval):19:in `item_url'

My best workaround has been to do:

link_to_remote "Show Details", {:url => item_url(@item) + "?
detail=1", :method => :get}

Which doesn't seem like the Rails way.

I'm not using a route like: items/1;detail and a helper like:
detail_item_url(@item), because I have mutliple parameters which I can
mix and match to change the view. It creates too many custom named