I picked up an iPhone 3GS last week, and spent a few hours trying to figure out how to access my EDS email on the iPhone using the Exchange support built in to the iPhone Mail client. Here is what I've learned so far.

EDS currently allows syncing Microsoft Exchange with iPhones (and any other SmartPhones AFAIK), although I've been told that it's "unsupported", meaning you must resolve any technical issues yourself. Fair enough.

Before you can begin configuring the iPhone, you must complete the following steps:

1. Login to the Gemini EDS Services web site on the EDS intranet.
2. Select your region (not sure if this works for all regions).
3. Navigate to the "Requests" page from the menu on the left side of the page.
4. Navigate to the "Mobile Workplace Services" page from the menu on the left side of the Requests page.
5. Navigate to the "Manage MWS" page from the menu on the left side of the Mobile Workplace Services page.
6. Check the "Subscribe to Mobile Workplace Service" checkbox.
7. Click the "Next" button.
8. You should see a confirmation page indicating that a request to enable Mobile Workplace Services has been submitted on your behalf.
9. Once the request has been approved by the system, you should receive an email confirmation, and you can now go and setup your iPhone.

To configure your iPhone, you must complete the following steps:

1. Launch the "Settings" app on your iPhone.
2. Select "Mail, Contacts, Calendars" from the Settings menu.
3. Select "Add Account...".
4. Select "Microsoft Exchange".
5. Enter your email address.
6. Do not enter your domain name (at least, I didn't have to).
7. Enter your username (EDS netid).
8. Click the "Next" button.
9. If you are prompted to verify the EDS certificate, click "Accept".
10. On the next screen, enter the EDS webmail address for your region (ex: uspl.webmail.eds.com)
11. Click the "Next" button.
12. Your account will now be verified, and, hopefully, you don't see any error messages.
13. You will be prompted to apply a security policy, which involves setting a passcode. I entered a numeric passcode, as this policy changes the iPhone's screen lock passcode and I'm not sure if the passcode entry screen accepts non-numeric values. If someone want's to try (potentially locking out their iPhone) and post the results, let me know :-)
14. Modify the Mail, Contacts, and Calendar settings.
15. Click "Done" to finish settings up your account.

That's it! Now you're ready to start using the best "SmartPhone" out there.