allow-update to localhost and (but not or) TSIG key

[Vasiliy Baranov]

Is it possible to allow zone updates only to those clients that access 
the server over the loopback interface and supply a specific TSIG key 
(looking for a setup similar to the default rndc configuration)? Will 
the following do the thing?

    allow-update { !{ !localhost; }; tsigkey; };

Thank you,
Vasiliy