$ perl -MDate::Manip -e 'print ParseDate("14 days ago")."\n"'
2003061110:22:53
$ perl -MDate::Manip -e 'print UnixDate("14 days ago","%Y%m%d")."\n"'
20030611
$ perl -MDate::Manip -e 'print localtime(UnixDate("14 days ago","%s"))."\n"'        
Wed Jun 11 10:23:04 2003