"Move to Resource" choices not including Portable class lib

I have a .Net class library (call it CL) which contains business objects (mostly just properties like string and int), and a portable class library ("P") in which I'd like to store some of the string resources for CL.  

I also have a silverlight business object assembly ("S"), which I would also like to share resources with the portable class library P.

When I add a portable class library to my existing solution, and add a resource file to it (it's not created via the Properties page) and use the ReSharper "Move to resource" quick-fix from a class in CL, it is not showing me the portable class library's (P) resource as a choice.  I made P's resources public and added a reference to it to CL.  

I must be missing something because I was able to create a small sample that works (ReSharper finds the resource library in P), but when I try to add a portable library to my existing solution, ReSharper only finds public resources from another assembly in the solution.

Question: What are the conditions under which ReSharper will "see" resources in other projects?  Public resources, Portable lib referenced in class library project, etc.?  

Thanks.

Don