This article describes how to go about removing and deleting an existing Exchange account on your iPhone. This can be useful if you need to rebuild your cached data or need to reconfigure your account.
If you have an early iPhone model or wish to use more than one mail account with your iPhone, you can add an IMAP account to connect to Hosted Exchange. This article explains how to setup IMAP with an Exchange 2007 or 2003 mailbox.
This article explains how to connect to your Lanlogic Hosted Exchange account to sync email, calendar, and contacts using your iPhone.