Trouble Importing my own card into Windows Cardspace

These days we are developing the identity provider component of the WSO2-Identity Solution and to get IE-7 identity selector to acquire tokens from our STS we need to be able to import a card generated and signed by our identity provider.

We generate cards with the help of the Apache XML-Security library. However Windows CardSpace is not able to accept the card and claims there's a problem with signature verification. But I can verify my cards using Apache XML-Security library.

I posted a question here in the "Windows CardSpace" MSDN forum. If anyone can shed some light on this issue please comment here or reply in the forum.