"no suitable daughterboard found" error on tunnel.py

I’m fairly new to GNURadio.

I have 2 USRP1 and two computers running Ubuntu 10.04.

I have a LFTX and a LFRX in my boxes that I’m hooking to a laser comm.
system.
When I run:

sudo python tunnel.py -f 10e6

I get the following:

Requested TX Bitrate: 100k Actual Bitrate: 125k
terminate called after throwing an instance of ‘std::runtime_error’
what(): No suitable daughterboard found!
Aborted

Why isn’t tunnel.py compatible with my LFTX?
Thanks.
-William

PS. Is there a GRC example of Tunnel.py foating around anywhere?