Web services were supposed to enable cross-application integration regardless of the underlying platform or language. While the promise is still there, today we still need tricks to make it work.
Windows Communication Foundation, or WCF, is an attempt to unify the various communication technologies available to the .NET runtime. Windows Communication Foundation. These include message queues, remote procedure calls, and web services. Web services, which use the SOAP protocol, can be a accessed from Perl using SOAP:Lite. Unfortunately, this library has not been able to keep up with the changing WS specs.
This has been illustrated in the January "State of the SOAP" post by lead developer Byrne Reese. http://www.soaplite.com/2007/01/state_of_the_so.html
Most SOAP toolkits as well have stablized along with the protocol. Relative to all those other toolkits, the status of this SOAP toolkit is fair to good. It differentiates itself from other toolkits by still being really easy to use for the majority of use cases. But as more and more people adopt document-literal as their preferred method of encoding, the roots and biases of SOAP::Lite in regards to XML::RPC begin to show and the toolkit is not as resilient.
As a result, SOAP::Lite has a number of known interoperability issues with more modern implementations of SOAP servers and clients.
Last month, Jeff Powers outlined what was necessary to access .NET WCF services from Perl using SOAP:Lite.
Details can be found in his post, How to consume a WCF service from Perl with SOAP::Lite. As this involves making changes to the WCF endpoint on the .NET side, it may introduce compatibility issues for pre-existing clients.