The relatively new use of 24:00 for a transition time is less than ideal. While zic can be unambiguous in its interpretation, it is just an interpretation even if that interpretation is correct/authoritative. The data is published and interpreted by other applications too and or read by humans.
To me the instant 2015-05-13 24:00 actually means 2015-05-14 00:00.... The instance 2015-05-13 24:00 does not really exist because at the very instant you roll over to 00:00 on the next date. But this is not zic's interpretation ?
Currently we have just Africa/Cairo and Asia/Dhaka using 24:00 as a transition time. Should not these be updated to avoid 24:00 and the ambiguity that arises.
Because of this ambiguity, as an international airline, we never schedule any flights to depart of arrive at midnight (00:00 or 24:00).
Anyway, the use of 24:00 _seems_ to have broken the JodaTime library.