However, the privacy mode requires a separate mail and address book app designed by Fujitsu, rather than the default email program and address book provided by the carrier.

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By default, it works with your Apple ID e-mail address, but you can add as many as you'd like from the settings application after verifying that you do indeed own the account.

ENGADGET: Apple iOS 5 hands-on preview

Consequently, although some users bend it to their will, most use it in a default manner (like myself) and merely read their mail, in or out of sequence, respond to some, ignore some and generally just leave their inbox an undifferentiated mess.

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Apple touted the service's ability to recognize when you're messaging someone else eligible for iMessages, but it appears to be limited to e-mail addresses at this point in the BETA. Delivery confirmation is turned on by default, but those of you who don't like the thrill of the chase will be happy to learn that there's an option to disable read receipts.

ENGADGET: Apple iOS 5 hands-on preview