title: Twitter Oauth URL encoding inconsistencies?
body: <p>I'm reading the walkthrough at <a href="http://dev.twitter.com/pages/auth" rel="nofollow noreferrer">http://dev.twitter.com/pages/auth</a> but there seem to be an inconsistency in encoding the callback URL. The callback is listed as:<br>
  oauth_callback
  - <a href="http://localhost:3005/the_dance/process_callback?service_provider_id=11" rel="nofollow noreferrer">http://localhost:3005/the_dance/process_callback?service_provider_id=11</a></p>
  
  <p>The signature base string is listed as:<br>
  POST&amp;...oauth_callback%3D<b>http%253A%252F%252Flocalhost%253A3005%252Fthe_dance%252Fprocess_callback%253Fservice_provider_id%253D11</b>%26oauth_consumer_key%3D...</p>
  
  <p>The callback appears to be double encoded here.  </p>
  
  <p>The signed Authorization header is listed as:<br>
  OAuth oauth_nonce="QP70eNmVz8jvdPevU3oJD2AfF7R7odC2XJcn4XlZJqk", oauth_callback="<b>http%3A%2F%2Flocalhost%3A3005%2Fthe_dance%2Fprocess_callback%3Fservice_provider_id%3D11</b>", ...</p>
  
  <p>Here, the callback appears to be single URL encoded. Why aren't they consistent?</p>