Incorrect TCP Checksums

While troubleshooting an issue I am having with a file not wanting to be
opened even though rights are assigned (but that part is another thread),
I've come across something odd. tcpdump captures (tcpdump -w xxxx.cap -s
5000) of traffic to the server shows every packet on the server as having
an incorrect checksum. This is seen in Ethereal on SuSE 9.3 by opening
the capture and viewing packet info. Can anyone else verify this for me?
A friend of mine at a local school system did a dump from his server and
gets exactly the same results.

Thanks,
Brian