Withings: getting oauth_callback to.. call back?

Question

Im working with the withings oauth implementation in hopes of retrieving stored values from scales. I can get the request token which I send back in hopes of getting the userid and the oauth_verifier passed back to my application.

What is happening is that if I pass in a full URL via the oauth_callback ( EG "http://some.site.com/myapp.php" ) the withings page displays the results on its page. But if I pass in just a page ( EG "myapp.php" ) withings will append this page name to its site and attempt to pass the parameters there (resulting in a 404). (EG "http://oauth.withings.com/account/myapp.php?oauth_params=..." ).

Other bits:
1. Code is in Perl
2. All oauth_signature values are HMAC_SHA1 signed
3. Any bits passed on the URL are url encoded using uri_escape

My questions:
1. Has anyone succeeded in getting data from withings?
2. Has anyone seen and overcome this problem with oauth_callback?

Answer 1

Turns out the answer is to url encode the address.. and then encode it again when you use it in the resultant signature and URL that you pass to withings.

I was just encoding it once.