WCF/Unity Interception not intercepting method call

Question

I want to use Unity Inteception with WCF to do Authorization on my method calls. I have followed articles to create an IInstanceProvider all the way to the ServiceFactory etc.

I have created a CallHandler to do the Authorization and hook it to methods with an attribute.

My problem is that it only intercepts the methods of the Service, and won't hook any other method in my BL. e.g. A method that the Service Method calls.