> >pc29: TCPv4 bad checksum from 1660a2cc:0050 to 818a01a3:0e62, len=20/20/40
>
> So far every occurrence of this message (that we can explain) has been
> traced to a faulty serial link. In some cases the UART could not cope
> with the incoming speed, tuning up the UART to match the modem fixed
> these. In others the finger is pointing at a problem with VJ
> compression, possibly a mismatch between Linux and some terminal
> server's implementation. For these, disabling VJ compression on pppd
> removes the problem.
Odd, this modem/UART stuff. I clearly forgot to mention that all this is
with a cheapo NE2000 clone, and no modem at all.