The automation options for primary and secondary talent automation aren't available for Classic Cataclysm. Is this a limitation with the forking of the addon or is this something that was missed?

You can do a custom script for this (Also choose "Disable in Combat"), just in case:

-- $EVENTS ACTIVE_TALENT_GROUP_CHANGED
-- $DESC Equips event on Spec Change
-- $SETTING spec={Label="Spec", Type="Number"}

if not isEquipped and GetActiveTalentGroup() == setting.spec then
    print('Equipping Outfit "' .. outfit.Name .. '"')
    equip = true
else
    return
end

Then there will be a setting for the "spec", you would choose "1" for the Primary spec and "2" for the Secondary spec

Just an update for here. It's still on my list. Since the workaround has been here, it hasn't been high priority. Hopefully soon.