A good module for finding the difference between two dates in days is Date::Calc. I used it to do something similar to what I think you are attempting to achieve. I wrote a script that checks a list of important days (i.e. - birthdays, anniversaries, etc) and emails me a reminder two weeks in advance. What can I say, I'm a forgetful person at times.

Anyway, the Date::Calc module can be used to find the number of days, as well as a huge assortment of other cool bits of information. I use the line $difference = Delta_Days ($current_year, $current_month, $current_day, $stored_year, $stored_month, $stored_day); and the Date::Calc module returns the days between. The module takes standard input: yyyy for the year, mm (0-11) for the month, and dd (1-X) for the day. I also use the standard localtime[3,4,5] to get today's date before sending it to the Date::Calc module.

Read up on the module and you'll discover its many uses. -Eric