By all means, please don't use cjson -- it's buggy as hell -- but if you must...

I was bit by the same bug as described here:
So I produced a fix, here is the patch:
And the full package now called 1.0.6:

And the changelog:

 Changes in version 1.0.6

 * Escape the solidus (forward slash '/') for encoding and unescape it for
 * Correct read/write solidus unit tests
 * Merge additional unittests from json-py for comments.  All these tests
   currently fail since comments aren't part of the standard json grammar.