Different behaviour on ActiveResorce with JSON or XML

I'm doing a request from a Rails app to another Rails app with ActiveResource.

When the format on ActiveResource is XML:

Content.find(:all)[0,2].map(&:attributes) => [   {"updated_at"=>Mon Apr 27 15:04:32 UTC 2009, "url"=>"www.google.com", "id"=>1, "created_at"=>Mon Apr 27 15:04:32 UTC 2009},   {"updated_at"=>Tue Apr 28 14:48:55 UTC 2009, "url"=>"www.google.com", "id"=>2, "created_at"=>Tue Apr 28 14:48:55 UTC 2009} ]

Nice and smooth.

But when it is JSON:

Content.find(:all)[0,2].map(&:attributes) => [   {"content"=>#<Content:0x2040d10 @prefix_options={}, @attributes= {"updated_at"=>"2009-04-27T15:04:32Z", "url"=>"www.google.com", "id"=>1, "created_at"=>"2009-04-27T15:04:32Z"}>},   {"content"=>#<Content:0x2040248 @prefix_options={}, @attributes= {"updated_at"=>"2009-04-28T14:48:55Z", "url"=>"www.google.com", "id"=>2, "created_at"=>"2009-04-28T14:48:55Z"}>}   ]

the problem is that to get an attribute in each Content object I have to do object.content.url instead of plain content.url.

Why is this happening? Is there any workaround?

Should it be better to post in the Rails Lighthouse?