Help with UPDATE

We are trying to run update.pkg 3 on a DecStation 5000/120
running Ultrix 4.3. When running the update.sh the following
error message is obtained

sh:illegal io

Can anyone tell us the problem.

Thanks

Anne Smith
Agriculture and Agri-Food Canada
Research Centre
Lethbridge, AB
Tel (403)-327-4561 Ext. 446
smitha@abrsle.agr.ca