Ref: 22340007
Title: Fixing an Incompatibility Between Maxess and Fujitsu VTAM
Date: 1/11/91

Copyright 3Com Corporation, 1991.  All rights reserved.

A client running 3+Open Maxess, version 1.0, attempts to get into the host,
which is a Fujitsu M360 running OSIV/F4 (Fujitsu's VTAM).  The client never
receives the VTAM banner.  If the user presses the Enter key, the error
"X443 Prog" is displayed on the 25th line.  If the host operator then
deactivates the LU and immediately reactivates it, the VTAM banner prints
and the login prompt is received.

The version of Fujitsu VTAM being used is

   OS    OSIV/F4
   VTAM  VTAM G EDITION 10 level 30

This version has been tested with other gateways, including Netlink SNA,
Memorex controllers, direct Irmalan, and Gateway Communications SNA.  All
have worked properly.

A trace of the interaction shows that Maxess properly sends an SNA Notify
command to indicate that the terminal is powered on (which the host
rejects--that's OK), but the host never sends a VTAM screen to the Maxess
client.  Then, when the LU is deactivated and activated and Maxess sends the
Notify command again (which the host rejects), the host finally sends a VTAM
screen.

This interaction is unlike true IBM VTAM because no screen is sent until the
LU is deactivated and activated.  The host does not appear to support the
SNA Notify command sent by Maxess.  If this is so, it could cause a session
cleanup problem.

As it turns out, the problem is caused by the version of VTAM that the
Fujitsu host is using.  To solve the problem, upgrade the version of
Fujitsu's VTAM to:

   OS    OSIV/F4 MSP edition 20
   VTAM  VTAM G EDITION 10 level 20    (Yes, 20 not 30)

