I added the info to the app.config but because that information is for runtime, it won't build. The error I get is :
I'm guessing it's not even looking at the app.config because it is just trying to compile.
I found something on SO with a similar problem.
Link
The class library in question is using .net 1.1 so the configuration is different and not sure if it even has a condition attribute for the references. Probably If I need to use the library again for higher .net versions I'll migrate it and have different build configurations for the different versions.
Doesn't really seem worth it at this point.
Maybe I'm doing it wrong though.