to get exchange working you first need root and either root explorer (paid app but worth the money) or es file explorer (free but you have to enable root privaleges inside the app. its under the settings menu)
1. navigate to system/apps and copy email.apk and email.odex
2. past these to your sd card as a backup
3. rename email.apk and email.odex to email.apk.old and email.odex.old
4. extract the files from the download and past them into the system/apps folder. (they should be Email.apk and EmailWidget.apk)
5. once done you can then go to email and try and setup an exchange account.
previously it only gave an imap and pop3 selection on the manual setup page. now it should include exchange as an option.
tested and working by me
again a big big thank you to the original poster/fixer the original thread is