Outlook 2000 Follow up reminders questio

I need Outlook 2000 to help me follow up e-mails sent to certain individuals. To achieve this I am using the Rules Wizard to copy the mails to a special Sent folder, and setup a follow up flag for 2 days time. This works – but when the follow up expires no warning is given anywhere. The messages show the follow up, and go red when the follow up expires – how do I trigger a reminder ?? It seems that Outlook is only tracking follow ups for the inbox – is this configurable anywhere ??
Any help very gratefully received!