I am trying a reminder mail system in perl, which automatically sends reminder mails to the responsible persons whoever not completed the task on time... I have the mail system in place and i am in need of logic to find the dates.

In nutshell, my requirement is, I have a due date for a particular task and i need to start sending reminder mails on WED and FRI of the two weeks previous to the due date. ie. If the due date is Dec 15 2008, i need to send mails on wed and fri from Dec 8 2008. And also while sending the last reminder mail ie. Dec 12 2008(Fri), i need to copy the mail to a higher level person as well.

Since the day of the due date varies, i cant able to find the correct way of finding when the last mail should be sent. I have gone through Date::Calc and Date::Manip modules and i am using ParseDate, Delta_Days and UnixDate subroutines, but still i was not able to grasp the correct logic?
Any help on this?