The general consensus around here for many years has been that this is a WONTFIX, unless perhaps it becomes more clear over time that, e.g., CDT is in much more common use than CST to describe the time during summer in Australia.  So far, there hasn't been a lot of convincing data on that, although some trends have been noted:
http://thread.gmane.org/gmane.comp.time.tz/5518/focus=5595