we are using unity for IOC and AOP, i think its much more flexible than your example with PostSharp. I will try to write a way for using SI with AOP over unity over Interception. I think that is, for sure, not easy like using AOP, SI, PostSharp, but much more flexible. Maybe we can integrate your postsharp example to a unity example. I just start to review now now you postsharp example to see, how you have done. How i said in my last post i think i have to do a little bir more with SI rather than the small work (and small possibilities) of log4net ive used until now. But its not wasted time!