So yet again we're left with the decision to either using some other method of enabling Notes across devices, such as using iCloud, else finding yet another way to hitting Mountain Lion over the head to get it to work with your OS X Server.
Now I've been able to get Notes going in OS X Mountain Lion 10.8.2 (12C60 - or later if you've applied additional machine specific updates) although there's one big big caveat. These instructions seem to only work in an account that has never had an IMAP account added to the Mail, Contacts & Calendars System Preference. The moment a mail account has been added I've been unable to get the instructions to work. That ultimately means you need to do this in a new user account. Bummer! I haven't put a great deal of time into figuring out what the true reason why this is, so if anyone does manage to figure it out I'd appreciate you letting me know :-).
If you're prepared to go through the hassle of rebuilding your user account this is what you do…
- As a first thing you will need to add your OS X Server account(s) to an iOS device. Once you have done this add at least message to the mail inbox and at least one Note.
- Create a new user account. This can be a local or network user account as it seems not to matter as far as I can tell.
- Restart your computer and log directly into the new user account you created. Do NOT log into any other account.
- Launch and quit Keychain Access. This is not technically necessary although it does stop some errors that seem to appear with no real pattern to it.
- Launch Mail and immediately add your OS X Server IMAP account as a standard account, do nothing more than confirm that you can receive mail.
- If you need to add more than one OS X Server account, meaning you want Notes enabled for more than the one account, add the additional account in Mail now via the Accounts tab in Preferences.
- Once you have confirmed that IMAP is working for all accounts, quit Mail.
- Open System Preferences and go to the Mail, Contacts & Calendars panel. If all has gone to plan you should see your mail account(s) added as a standard mail account rather than an OS X Server account. Additionally, and this is the important bit, you should also see that both Mail and Notes enabled. If you see Notes enabled continue on. Otherwise, you need to start over by totally deleting the user account. Notes needs to have been automatically enabled - if you need to manually enable Notes at this point it isn't going to work.
- Add your OS X Server account(s) as an OS X Server in the Mail, Contacts & Calendars System Preference and enable all the services you want with a minimum of enabling Mail and Notes. Yes this is "doubling up" but we'll clean this up later. You should also notice that, yet again, when you go to enable Notes it'll just sit there with a spinning wheel not enabling. Don't worry about this… it is in fact enabled already.
- Quit System Preferences, reopen System Preferences and go to the Mail, Contacts & Calendars panel.
- You should now see that under your OS X Server account(s) that Notes is now enabled. Go to the standard mail account that was originally created and delete it. You should also note that both Mail and Notes have been disabled here (they were disabled by the enabling of the OS X Server account).
- Launch Notes. You may find it stalls or crashes on the first launch and you should also get an initial database failure. Upon relaunching Notes you should now see your OS X Server account(s). And now we're done!! :-D