Want to see how long you spent on a particular call? From the Call Log, select the call, then select Details. Keep in mind that your billing statement may vary slightly from the information you see onscreen. Usage is charged based on your calling plan., and calling plans vary.
Barring calls
Call Barring lets you prevent unauthorized calls on your Treo. This feature may not be available on all mobile networks.
You must enter your Call Barring password every time you change your Call Barring preferences. Contact Cingular Wireless if you do not know this password or if you need more information.
1.Open the menus 
.
2.Select Options, and then select Call Barring.
3.Select the onscreen pick lists, and then select your Call Barring preferences.
4.Select OK.
Viewing minutes usage
1.Select the Call Log favorite button.
2.Open the menus 
.
3.Select Totals from the Record menu.
4.(Optional) To reset the counters to zero, select Reset Counters.
5.Select Done.