Rackspace just released the public beta for the UK version of Rackspace Cloud. The UK Rackspace Cloud doesn’t have the same auth server as the US Cloud so there is a few change you need to do to support the UK Rackspace Cloud. This is the same way Amazon has different zone for EC2 we have now different geographical zone between the US and now the UK.

If you access directly, you just need to adjust the Auth URL in your code to go to :

https://lon.auth.api.rackspacecloud.com

instead of :
https://auth.api.rackspacecloud.com

The language binding provided by Rackspace has all been updated and available from github :

For Python CloudFiles :

cnx = cloudfiles.Connection(api_username, api_key, authurl="https://lon.auth.api.rackspacecloud.com/v1.0)

For Python CloudServers :

cloudservers.CloudServers("USERNAME", "API_KEY", auth_url="https://lon.auth.api.rackspacecloud.com/v1.0")

For Ruby CloudFiles :

require 'cloudfiles'

  # Log into the Cloud Files system
cf = CloudFiles::Connection.new(
                                :username => "USERNAME",
                                :api_key => "API_KEY",
                                :authurl => "https://lon.auth.api.rackspacecloud.com/v1.0"
                                )

For C# CloudFiles :

UserCredentials userCreds = new UserCredentials(new Uri("https://lon.auth.api.rackspacecloud.com/v1.0"), username, api_key, null, null);
Connection connection = new com.mosso.cloudfiles.Connection(userCreds);

For Java CloudFIles add a cloudfiles.properties file in your classpath with this content :

username=username
password=apikey
auth_url=https://lon.auth.api.rackspacecloud.com/v1.0
connection_timeout=15000

and you would be able to access it like this without any argument to the constructor :

FilesClient client = new FilesClient();
client.login();

For non rackspace binding I have sent a patch for Apache libcloud :

https://issues.apache.org/jira/browse/LIBCLOUD-66

which when integrated would allow to do something like this :

for jclouds you can just pass the auth server like this for cloudfiles :

and like this for cloudservers :

for Ruby Fog :

require 'rubygems'
require 'fog'

rackspace = Fog::Rackspace::Storage.new(
  :rackspace_api_key => "",
  :rackspace_username => "",
  :rackspace_auth_url => "lon.auth.api.rackspacecloud.com"
)