[olpc-help] Rx invalid frag - what's going on?

[spider3]

When I do:
/sbin/iwconfig
I see very large and rapidly growing counts of Rx invalid frag in the
status. Sometimes there's even an increment of them between the
two interface status reports (msh0, eth0). Looking at other devices on the
same WiFi net, their counts are all 0.

Things seem to be working fine otherwise.  Still, anything happening at
these rates is consuming some resources somewhere, so I'm curious
and wonder if I should disable something, etc.

This is a G1G1 still on the original factory software. It's a WEP protected
(HA!) net with an ancient Linksys WRT54G running a very old firmware
version (if it ain't broke why fix it).

TiA,
jay