Lastly, what zork was talking about, the "possess bars":
These are just the pet bar replacing the normal action bar, with the action ID's 133-138, and [pet] works with it.
The bad thing however is that normal pets also use the [pet] state, and will interfere.
Also, if there is no spells given from the bar (example: Dominate Mind on a enemy player) will result in the actionbar not changing.
This means we also need a proper state for this.
Also, while we are discussing states, I found that there is no way to detect wether a druid in cat form is really in stealth (Prowl).
Both Prowl and Shadowmeld (night elf racial) makes [stealth] returns true.
Even if we use [form:3,stealth], Shadowmeld still works in cat form, and it will make the condition return true.
Conclusion, we have no way to detect if the Prowl-only abilies such as Pounce is really usable.