node.js plugin: upgrading to a new version of node can leave IDEA looking at the old cached source code

IDEA 11.1.5, build IU-117.1043, Java 1.7.0_21 64-bit.  Node.js plugin 0.2.2

I use nvm to upgrade and select my version of node.js. I also update the IDEA node.js binary and source locations and keep the debug configuration up-to-date. 

But when I have upgraded to a new version of node (currently 0.10.5), and run the debugger, I often find that IDEA is using a cached version of the old source code (in this case 0.8.22 in system/extLibs).

This causes very strange debugging behavior if you need to step into node's code. 

Workaround: exit idea and remove every node.js source directory from .IntelliJIdea11/system/extLibs/ except the source for the version you are currently using.  Restart IDEA and it will now find the right source code.

--JB