Secure a WF4 Workflow Service with ADFS2/WIF?

I have a .xamlx Workflow Service that I would like to secure so that it can only be called by clients that have obtained a token from my STS (ADFS v2.0). Normally this is very easy to do if you're us开发者_StackOverflowing a "Web Site" project template, and you've added a .SVC service - the "Add STS Reference" wizard will find the service you want secured and will secure it individually for you as a relying party.

Problem is, when you do "Add STS Reference" to the Workflow Service application, all you get is "passive redirect" security, not active federation which is what you need when securing individual services.

Anybody know how to do this?

Looks like this might be the answer: http://zamd.net/2010/07/04/using-wif-with-workflow-services/