Methods, systems, computer program products and data structures are described which allow a client to communicate with a server even though multiple proxies that require different authentication data must be traversed to allow such communication. In operation, the client first authenticates to a first...http://www.google.co.uk/patents/US6839761?utm_source=gb-gplus-sharePatent US6839761 - Methods and systems for authentication through multiple proxy servers that require different authentication data
