Vista - Import of a Signed SAML assertion in SamlAssertion class (May CTP)

Hi,

I have developed a STS on a device that generates a SAML Assertion
which is signed. I have checked this XML assertion with an original
created by WCF with the same parameters. I'm willing to use this
SAML/RSTR using a WCF proxy but I'm building the RSTR/SAML without
using a .NET framework on PC, so I cannot use any class of WCF to build
this RSTR/SAML, I get a XML text representation.

They perfectly match (Digest and Signature are perfectly the same).

I can import this SAML when it's not signed in the SamlAssertion using
ReadXml, then I had the SigningCredential and it works perfectly.

However if I import the same way the Signed XML it is imported but the
RSTR built with this SAML is rejected by WCF.

I found out that when I import the Signed XML, the field
SigningCredentials is not initialized by the import method, while the
signature is verified. I decompiled the code of WCF and apparently the
import of the XML assertion doesn't initialize this filed, which causes
it to be rejected at WS-Trust level of WCF.

Could anyone of MS tell if this is a bug in the code of
SamlAssertion.ReadSignature or if there is a way to do it that works?

In the same maner I built a complete RSTR including the signed
SAMLToken, that I could verified with the equivalent using WCF and it
is also rejected by WCF after I construct a Message object using the
CreateMessage method to import the XML data.
This worked with the February CTP with a different SAML token using
Combined Entropy as Proof-of-Holder but doesn't work anymore with the
May.

Anyone out there is trying to do some interoperation work with WCF and
InfoCard.
Thks & Rgds
Olivier Rouit
Gemalto
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