"xmltooling::ValidationException" using ADFS 2.0 IdP with sp.testshib.org

[xenophon\+shibboleth]

Hi again,

I'm working through an ADFS/Shibboleth interoperability testing guide at
http://technet.microsoft.com/en-us/library/gg317734(v=ws.10).aspx.  The
first scenario has ADFS 2.0 as the IdP and Shibboleth as the SP, so I
decided to try it against TestShib2.  After a successful authentication,
sp.testshib.org returns the following error:

	xmltooling::ValidationException
	TestShib encountered some sort of error while processing your
request issued at Fri Oct 26 12:30:06 2012 .
	xmltooling::ValidationException at
(https://sp.testshib.org/Shibboleth.sso/SAML2/POST)
	X509SerialNumber must have TextContent.

I see urn:oasis:names:tc:SAML:2.0:status:Success messages in the SP's
log file, but no errors.  I didn't find anything about this error
message in several different web searches.  Has anyone else been able to
get an ADFS IdP working with TestShib's SP?

Best wishes,
Matthew

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