SOAP Failure when Transitioning from ASP.NET 1.1 to ASP.NET 2.0

[Steve R.]

We have been transitioning our web services from ASP.NET 1.1 to ASP.NET 2.0
as we migrate to vs.net 2005. The web services are accessed from a Linux box
using SOAP 1.1. Web services that pass simple parameters and receive data
sets work without a problem on both ASP versions.
Services that pass in a dataset, using SOAP, work properly on version 1.1
but fail on ASP.NET 2.0 with the error message:

Internal Server Error 500

The web services have been developed in C#. We tried switching to SOAP 1.2
but got the same result. We validated that the SOAP format matches that shown
when the web services are accessed using a browser.

Is there a new setting required in the Web.config file or are we missing so
new security setting?

Any help would be appreciated.

Steve