iPhone 3G set time automatically? I've noticed on an old iPhone 3G I keep around for testing that the Set Automatically option in Date &amp; Time doesn't work. This iPhone has a SIM card, but it has been deactivated by the carrier after upgrading to a newer model which uses a different size card.

I assumed it would work using Network Time Protocol (NTP), which means it should be able to sync the time over WiFi. But I haven't find any documentation on this.

I keep this iPhone around for testing, so it only comes out of the drawer every few months. Keeping it fully charged isn't a realistic option.

This phone is running the final version available for it, iOS 4.2.1 (8C148).

My question, then: Can I make this work? Failing that, is there documentation available that says once and for all that it can't be made to work?
&quot;Set Automatically&quot; takes the time from the cellular network. If you remove the SIM card (or just keep the phone in airplane mode with Wi-Fi enable), the time will never get updated.
From the iPhone User Guide (available in iTunes):

If iPhone is set to update the time automatically, it gets the correct time over the cellular network and updates it for the time zone you’re in.
Some carriers don’t support network time in all areas. If you’re traveling, iPhone may not be able to automatically set the local time.