Recently Apple apparently changed the way MobileMe Calendar syncs with your iPhone. Resulting in hit or miss solutions for it to work. There’s quite a few threads and posts out there with people asking how to fix it or even what to fix.

Enable MobileMe sync in a few easy steps:
1. Go to settings > Mail, Contacts, Calendars
2. Access the MobileMe account
3. Disable Calendar sync and go back to Mail, Contacts, Calendars
4. Choose ‘Add account’
5. Choose ‘Other’
6. Choose ‘Add CalDAV Account’
7. Fill in, press next when done;
- Server: cal.me.com
- Username: yourusername (without @me.com)
- Password: yourpassword
- Description: Some name or recognizable thing (eg. MobileMe Calendars)
8. Your account will be verified with MobileMe and should work within secongs. Verify and download the calendars in iCal on your iPhone.

Unfortunately this account does not use Push, but uses Fetch instead.
This is a semi automatic method triggered in preset intervals. I’ve set mine to 15 minutes.
You can change this in Mail, Contacts, Calendars under ‘Fetch new data’.

Have fun!