memcache key suggestion

[brianmercer]

I would like to use Nginx to retrieve pages placed in a memcached bin by Drupal caching.

The Drupal key appears to be:

  cache_page-http%3A%2F%2Fexample.com%2Fcontent%2Fquadrum-utinam

Using

    ...
    set   $memcached_key   cache_page-$scheme://$host$uri;
    memcached_pass   127.0.0.1:11211;
    ...

does not produce a match.  I get:

  key: "cache_page-/content/quadrum-utinam" was not found by memcached while reading response header from upstream ...

Is that an encoding problem?

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,18166,18166#msg-18166