By default the Treo 700 is configured so that the touch screen is active even when you are making calls. This can lead to some unexpected results when you are using your Treo as an actual phone. When your phone is against your face, and your face comes in contact with the touch screen the most likely outcome is a dropped call. This only has to happen to you once before you want to change this behavior. You can disable the screen during calls to keep this from happening. The keyboard, buttons, and navigator will still work so you can still use your Treo to pull up information when you are on a call, it just disables the touch screen.

If you are running Windows Mobile on your Treo, you can disable the touch screen by going to "Start -> Settings" and then selecting the "Personal" tab and then selecting "Keyguard". Set the "Disable Touchscreen" option and then click OK.

Your Treo touch screen will then be disabled when making calls. No more lost calls for you.