Problem: My iPhone requires a passcode when syncing with Exchange 2007.

This happens because Exchange 2007 security for mobile devices is enabled by default. You can turn it off by the following method.

Solution
1. Open Exchange 2007 Management Console as an administrator. (Navigate Start > Programs > Microsoft Exchange Server 2007.)
2. Navigate to "organization configuration," then choose "client access."
3. Right-click on Windows Mobile Mailbox policy and choose "properties."
4. Select the password tab and uncheck "require password."
5. Apply and OK your selection. Now you can configure your exchange account on your iPhone.

Note: If you have already configured an Exchange account, you must delete it and reboot your iPhone and then add it back.

Here are the steps to restore your iPhone battery and performance to pre-ios4 luster.
1. You must set your phone to factory defaults: on the iPhone choose Settings, General, Reset (at the bottom), Erase all Content and Settings. Be aware it will take several minutes to reboot as a new phone
2. Attach your iPhone to a computer running iTunes and sync as a new phone without syncing music or contacts.
3. Sync ios4 compatible apps
4. Sync your e-mail, contacts and calendar
5. Sync your music and pictures. This is the final step because it is the most time consuming. I suggest you enjoy a nice hot cup of coffee whilst you wait.