I've knocked together an implementation of SysV/POSIX timezone specifications for DateTime. Code is at <http://www.fysh.org/~zefram/tmp/SystemV.pm>. This is my first go at implementing anything in the guts of DT, so experts here please check that I'm using the interfaces correctly. I don't quite follow what the semantics are meant to be when a DT object has its timezone changed.
I'm not clear on which DateTime methods a timezone object can rely on, in the arguments it is given to the _for_datetime methods. I need to do Gregorian arithmetic even if the DateTime isn't Gregorian. I used only ->utc_rd_values and ->local_rd_values, and then called out to my Date::ISO8601 module to do the date arithmetic. Is it OK for me to put this on CPAN? -zefram
