I knew theoretically it was possible to use an iPhone or itouch with an Exchange 2003 Server, using Outlook Web Access, as I have successfully done this with several Blackberry’s. I have also found some instructions on the Apple website about using the iPhone or iTouch with Exchange directly, but not via Outlook Web Access.
I have successfully managed to do this now, and it works very well indeed. This is how i did it:
http://www.impirius.co.uk/Support/How-to-setup-an-Exchange-email-account-on-an-iPhone-or-iTouch-using-OWA.aspx
I have created a separate page for this there's a bit too much information for a blog article!