A workaround to force the rotation option to appear in Mac OS X:
- Open System Preferences, holding down the Command+option keys
- Hold down the Command+Option keys while clicking on the "Display" icon
- A "Rotation" menu will appear on the right side of the Display preference pane.
- Appropriately set the rotation in the drop down menu
- Close System Preferences to save the settings
Note, if this does not work, quit the System Prefs application completely and use the command-option key sequence, the very first time you access the Display prefs. After the Rotation popup appears, going out of the Display Prefs, then coming back, does not require holding the command-option keys down.