MT3000 All clients 'Unknown' in AP mode

The “Clients” tab from the main web interface reports all clients as “Unknown”, i.e. it does not seem to perform a DNS lookup for them. My MT3000 is running in Access Point mode if that can help. I have tried setting DNS servers and adding names to /etc/hosts but it does not help. I could certainly populate /etc/config/gl-client myself but there must be a way to do that automatically.
Any help appreciated, thanks!

In AP mode, the router cannot detect the hostname of the device.

Exactly. Why not try a DNS lookup to associate name to IP address?

Looks like IP/name conversion works fine in Luci/Overview.