My partner's M0n0wall, running 1.3b3 or 1.3b4 (tried it both ways) gets
a series of messages in the log something like this: 

vr0: link state changed to DOWN
vr0: link state changed to UP
vr0: link state changed to DOWN
vr0: link state changed to UP

This goes on and on, sometimes multiple times per minute.  Can someone
point me in the right direction for debugging this?  What causes the
state to change?  Could external forces, like a bad switch cause this,
or is this more likely to be internal to M0n0?

Thanks for any advice you can give me.

Lynn Grant
(proud owner of 3 M0n0walls)