Connected Hosts Shows 10.72.0.1 Is this an error?

[1an]

I have a WRT54GL running Gargoyle Version:1.3.5

On the Connected Hosts page, this entry is always present.

Hosts With Active Connections
Hostname Host IP Host MAC
(unknown) 10.72.0.1 unknown

I gather that 10.72.0.1 is an internal address used by the router?
Why does this show up on the Connected Hosts list?

I hadn't worried about it, but as I have quotas set up including ALL_OTHERS_COMBINED, this ip seems to get included in this quota. If I set the quota too low and it reaches 100%, all hosts get served the Gargoyle login page rather than the url requested by the browser.

Thanks for any information

Ian