How do I use an external diff tool to compare *folders* in Intellij IDEA ?

I am attempting to use an external diff tool (Beyond Compare) to compare folders in Intellij IDEA 13 (EAP Build #IU-133.471).

Settings

My Intellij IDEA settings are as follows:

Documentation

Relevant documentation for Beyond Compare : here and here

Intellij IDEA's doc on the subject : here

Herein Lies the Rub

And here is what happens when I select two directories and press Ctrl + D (the shortcut to

Compare Directories

) :


The same works fine when comparing files:



I have attempted using the current stable version of both Beyond  Compare (v3.0) as well as Intellij to no avail. I have had no joy after  appending the parameters

%1 %2

etc. to the

Path to Executable

either.


Can you think of what I might be missing ? Have you used an external diff tool to compare folders in Intellij IDEA ?

Thanks!