VOTable 1.3 is the current standard, and the BINARY2 data format is the one most likely to be used as the LSST default. BINARY2 adds proper support of NULL values, in particular.
The action is to upgrade the Java support libraries used by Firefly to a version that provides full support for this. I suggest at least STIL Version 3.2-1 (see http://www.star.bristol.ac.uk/~mbt/stil/sun252/history.html).
This is required for LSST and also has to work in production for IPAC since attempts to access external services via Firefly are increasingly likely to generate data in this format.
This may be related to the "bit" bug fixed in STIL Version 3.0-13 (17 Aug 2015).