docusign failing

[Ted Fisher]

We have recently started authenticating docusign from our idp which has been working fine.  Our apps people have found though that when they review a first document it redirects to our idp and completes authentication, but then when they open a different document it redirects to the idp and /idp/AuthnEngine throws a 500.
I've increased logging to quite a bit of debug and I don't see any indication what is causing the problem.  No error gets logged.  I've looked at the SAML request (using SAML tracer) and nothing looks amiss that I can see.  I'm stumped as to what is causing this and how to correct it.

Any suggestions?

Thanks.

Ted F. Fisher
Information Technology Services