Illegal ARPs from AT&T 3B1s. How to stop those?

[Craig Paul]

We have some AT&T 3B1s (no comments, please) running Unix System V3.1
for the Unix PC, along with Wollongong's Win/tcp 1.4

The machines are emitting illegal ARP requests. Killing all internet
software doesn't help, so say the people in the department responsible
for those machines.

Suggestions? Please mail to me directly, as I don't read this newsgroup.
Thank you!