When the iPhone was first released, there was a lot of hype about it offering true push email on the go for users. Everyone hoped that this would be provided through the IMAP IDLE extension, which would have made the feature available to all IMAP email services that support IMAP IDLE.

In fact, it turned out that this service was available first of all only to Yahoo.com mail users, and then later in the iPhone 2.0 software to Exchange users, and it doesn’t use IMAP IDLE.

The best my iPhone can do is poll my IMAP accounts through its “Fetch” feature every fifteen minutes.

Hoping to overcome this limitation, msgpush.com offers iPhone users the option to receive faster notification of new email by providing each user with a “fake Exchange account”.

Here’s how it works: You sign up at msgpush.com. It monitors your IMAP account through IMAP IDLE, and then sends notification of new mail to your iPhone through the Exchange protocol. Sounds clever, but there are some caveats:

1. You need to surrender your username and password for the IMAP account to msgpush.com, which not everyone will feel comfortable about.
2. You need to set up a new Exchange account on the iPhone to receive these notifications. But Exchange only allows you to run one profile at a time. So, if you have one configured already (as I do for my Zimbra account at work), this service is a non-starter.
3. It doesn’t actually read or push the email itself, only a notification that the email is waiting in your account’s inbox. So you still need to retrieve the email manually.
4. It’s still in beta and, according to some users, is proving a little erratic.

Still, even with these quibbles, it may be the solution that some users who can’t wait fifteen minutes are looking for.

I haven’t tested it (see 2. above), but you might like to. Sign up at the msgpush.com web site.

[With thanks to the Fastmail blog and forum posters ]

UPDATE: Tom Yager writes more on push email and the iPhone 3.0 software at InfoWorld. imap, imap idle, exchange, iphone, pushmail, notifications, Similar Posts:

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• IMAP-IDLE Plugin for Mail.app updated
• Mail.app IMAP IDLE plugin
• IMAPCheck: Plugin for server-side mailboxes
• Gmail IMAP, Mail.app and iPhone Mail in harmony