Synchronica sent me this email...
Synchronica’s Mobile Gateway product is SyncML gateway. Version 3.0, soon to be available, adds an IMAP/SMTP gateway so that both SyncML (PIM) and IMAP (email) are supported in the same product. We support SyncML on many handsets where it is built in, and through clients on Palm OS and Windows Mobile devices.
We are able to support mail only on the iPhone, as the iPhone has an IMAP client built in. Unfortunately, Apple has not chosen to use the industry standard SyncML protocol to sync calendar and contacts on the iPhone. Although we do have a desktop Mac OS X client that we could potentially leverage for the iPhone, Apple has been clear that they will not provide a mechanism for third parties to install applications (like a SyncML client) on the iPhone in the near future.
Since we can’t install a client, and, since Apple has not made public what they are using to sync calendar and contacts from desktop Macs and PCs over the USB cable, there is no option at the moment to support PIM data over the air. This applies to Apple as well as all third party developers.
So, at the moment version 3.0 of Mobile Gateway can do PIM data + email on 1) handsets with built-in SyncML and IMAP clients, 2) Palm OS Treos and 3) Windows Mobile devices. We can only do email on the iPhone due to the limitations Apple has placed on the device and what developers can do with it. Sorry that I don’t have a better answer.