Cross platform interop: WS-I Basic Profile....
Building Interoperable Web Services: WS-I Basic Profile 1.0 is intended to help software architects and developers design and code Web services that are interoperable across multiple platforms. This was the goal of the Web Services Interoperability (WS-I) organization in the Basic Profile version 1.0 which was officially ratified on August 12, 2003. In this patterns & practices release, we will show you how to create and consume Web services that conform to those guidelines.
To find out more, take a look on MSDN.