TODO list for Perl module DateTime

* leap seconds

- what's the relation between UT1 and MJD/JD ?
  see:   http://hpiers.obspm.fr/eop-pc/earthor/utc/leapsecond.html

* strftime method

- more tests for other languages

* sub-second resolution

- more tests: add/subtract/compare

- add microseconds, milliseconds to:
      DateTime new/truncate/accessors
      DateTime::Duration new/accessors

- jd, mjd should return nanosecond precision?

* Other

- overloading for DateTime::Duration: division? (duration / int).

- document RD days/seconds(/nanosecs?) in a separate document that
will be the reference for DateTime.pm internals, as well as being
useful for other calendar implementors.

- Time::Local is now a core module, with no CPAN existence.  But the
version that works best is in 5.8.0, and not otherwise available.

- thorough tests for subtraction & addition overloading

- by default, reject out of bounds datetime values (minute 75) but
offer a "normalize" parameter that will wrap these.


NOTE TO FUTURE DEVELOPERS:

Attempting to implement add_duration in XS actually seemed to slow
date math operations down.  Sad but true.
