Hello!
I'm trying to create the following scenario:

1. Internet Explorer client initiates a command to presentation server.
2. presentation server calls a web service.
3. web service is configured with a policy which requires x509
signature - returns an exception along with the digest value needed to
be signed.
4. Internet Explorer receives the 'signature request' and signs it
using a smart card and CAPICOM. client automatically retries the same
command and sends the same button click to presentation server.
5. presentation server calls the web service and this time the custom
client policy assertion detects the browser signed the message and
builds the ws-security elements.
6. service accepts the request and everyone are happy.

Right now I'm a bit stuck in stage 5.
I'm able to load the client certificate from the browser and construct
an X590SecurityToken,
from that I create a MessageSignature and try to manually create the
reference to the soap body and insert the SignatureValue to what the
client signed in CAPICOM. the problem is that when I finish it's still
trying to sign the message using the x509 security token and naturally
throws an exception about only having the public key and not the
private.
Any idea how I override that process and just insert the signature by
myself? I don't mind veryfying it by myself in the server side using
another custom policy assertion.

Thanks!

Avner Peled
avnerus@gmail.com