getQuantityString not replacing the format with the value

I want to uses the plurals resource to produce a quoted number like "9".

In my plurals.xml:

<plurals name="posts">
  <item quantity="other">\"%dd\"<\item>
</plurals>

The code:

String text = res.getQuantityString(R.plurals.posts, meUser.postCount); 

When the postCount is 9, why does text turn out to be "%dd" and not "9"?

From the Android docs:

When using the getQuantityString() method, you need to pass the count twice if your string includes string formatting with a number. For example, for the string %d songs found, the first count parameter selects the appropriate plural string and the second count parameter is inserted into the %d placeholder. If your plural strings do not include string formatting, you don't need to pass the third parameter to getQuantityString.

ie res.getQuantityString(R.plurals.numberOfSongsAvailable, count, count);

Just in case anyone has a brain-fail like me today and still cannot get it working.

I had accidentally left my emulator in a non-English locale which meant my "one" translation was being ignored!

(Only the "other" entry was being used in my case)