$ perl -T -MDate::Manip::DM6 -E 'say $Date::Manip::VERSION'

##</code><code>##

$ DATE_MANIP=DM5 perl -T -MDate::Manip -E 'say $Date::Manip::VERSION'

$ DATE_MANIP=DM6 perl -T -MDate::Manip -E 'say $Date::Manip::VERSION'