For Windows Comet by Natara has a desktop app to importing and tracking the Call History from the Treo.

I liked this but no Mac version. So I have built an app for the Mac to do this. "Treo Call History Archive v 1.0" is now available. Some features included:

easy Import of history
export as HTML
list by date, number, contact, time of call, duration of call, roaming & status (outgoing, incoming or missed)
Find by (month, day, year, date range, contact and more)
update by matching existing, and adding new records
sort each row in list by ascending and descending order
print and print preview
totals in Hours, Minutes, Seconds and a separate grand total of Minutes

The initial release is for OS X. There will be a OS 9 version soon.

The is Freeware so NO support question via email. Please use this thread at Treo Central and I will try to respond.

Download and How To