Big problem (Novell 3.12 + Oracle 7 + Win95 + TCP/IP

We have a network problem.
Our network architecture is as follows :

Our network is Novell Netware 3.12 based, and made of 2 subnets. We have a router on one of the first subnet that allows to connect to our Oracle 7 database (on a HP9000) through a leased line. We use TCP/IP v3.00h to connect this base.

The problem :
There's no problem on the first subnet, on which is pluged the Megapac router. On the second subnet when connected to the database, the openning of a file makes a ORA-03113 error. We managed to resolve this problem on stations based Win 3.11 by adding two parameters in the LanWorkPlace NET.CFG file : TCP_WINDOW=17856 and TCP_MAXSEGSIZE=1024. The problem is that we cannot change such parameters on Win95 based machines except when running VLMs which is not conventionnal memory friendly and slows down the CPU. We could not find which parameters to change in the Win 95 TCP/IP stack.
The SQL*NET release we use is 1.1.7.10.4, the declared TCP VENDOR is MS Windows NT TCP/IP. We tried other TCP/IP stacks with MS Novell Client, with no succes. We also tried SQL*NET v1.1.9.0A, with no succes either. The Oracle Installer release is v3.0.10.3.1 with Required Support Files v7.0.16.4.4D
What has changed since all this worked well ? The database machine and its OS version.

We called our network support, who could not help us. They called Novell, with no succes. Those who run our database (a world well know consulting firm) could not help. They called Oracle who could not help. We called Microsoft, who could not help. The MS Engineer we talked to did not even know about changing TCP/IP parameters in the registry base, using REGEDIT. Our next try will be a pray !!!

If anyone can help...

-- 
                        Marc "polom" Savard
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