I did have others setup with bridge that work just fine.
The reason to use the bridge for this client in specific was because the vlans of the wireless did not exist on the virtualization hypervisor.
However, on this month will be necessary to implement RAP with others APs, so is mandatory to create the vlans now, and the bridge setup will change to tunnel.
But this problem with IPs look like more a bug than a limitation, I cant see why the APs having the ARP and IP tables, performing the authencation and etc are not giving back to the controller this kind of basic information.
And about the limitation of the bridge setup, I think is more like a question about Aruba is not willing to invest on the code and on this kind of implementation, because the APs on Instant Mode are able to do almost everything that a controller do, why we will loose functions if the traffic dont go to the controller ?