The features need to be displayed as LINKS or BUTTONS
The first link/button would add 3 days to the date in the field
The second link/button would add 7 days
The third link/button would add a month to the link.
See Example here
[url removed, login to view]
So if the date was 20081230 (December 30th 2008 - formatted as YYYYMMDD) and you clicked the 3 day link/button it would change the value from 20081230 to 20090102. If you clicked the 7 day link it would change the date to 20090106 and the 1 month it would change it to 20090130.
If you have questions please PM me