I setup my speedtouch 780 to accept/forward WOL packest to my Home PC from Work..
I believe that the BT HomeHub is a speedtouch 7G and configuring it is basically the same, although I can't confim it.
From memory All I had to do was
Telnet into the Speedtouch.
and at CLI execute
:ip arpdelete intf=LocalNetwork ip=
:ip arpadd intf=LocalNetwork ip=
This creates a static arp entry otherwise the Speedtouch seams to forget where the PC is conncted.
then execute
:service rule add name="Wake on LAN" protocol=tcp portrange=7-9
:service rule add name="Wake on LAN" protocol=udp portrange=7-9
:service assign name="Wake on LAN" host=
These last 3 can be setup from the web interface "Game & Application Sharing" if prefered.
Details on how to send the WOL packet can be found here
http://www.depicus.com/wake-on-lan/woli.aspx
The PC will also need to be setup with a static IP Address or to always get the same address from DHCP.
Hope this helps