Insufficient Memory on Domino 6 on V5R3

I will try and do my best to explain the problem but it has been going on 
for about 6 months now so I might leave something out.

Here are details of the system
iSeries 270 with 3gb ram, 1 partition, ~180gb of storage
We are currently running a Homegrown accounting system (all green screen), 
Domino and websphere.  We don't use websphere currently but it is running.

We started getting "Insufficient memory" on the clients back in April.  We 
tried just restarting notes and that didn't help, I think we had to IPL to 
get domino to work again.  We have since fund out how to clear the shared 
memory through iSeries navigator, so we don't have to IPL it just shutdown 
Domino, cleared the shared memory, start Domino. We would be good for 
about 3-4 weeks before it would happen again.  At the time we were running 
Domino 6.5.   Our business parter suggested we upgrade to 6.5.4 and 
upgrade the ram (we had 2gb, now 3gb.)  we have since done that and the 
errors and domino lock ups come more and more often now.

We have been dealing with IBM but they have not really been any help.  We 
have been sending them memory dumps and other debug info but have not 
gotten a satisfactory answer from them.

We found the ConstrainedShMEM setting on notes.net and set it to 2gb. 
Since then we still get the error messages but the server is not totally 
locked up like it did before. We can actually get into Domino and do some 
poking around before we restart it.

Our NSFBufferSize was set to 300mb and the 
Database.Database.BufferPool.Peak.Megabytes = was always at 300mb.  We 
have since changed it to 500mb and it is usually at 498 now. Should we 
increase this more?

For the last month it has been crashing every Tuesday morning.  The 400 
IPL's on Monday morning and Domino shuts down everynight from 1am to 4am 
for backups. So it IPL's on Monday morning, runs fine all day monday. 
Shuts down Tuesday morning, backs up Domino, restarts at 4am.  By ~5:30am 
on tuesday we start receiving the "insufficient memory errors" in the log 
file, but it doesn't yet effect the end user.  By about 7:30 or so end 
users start getting the message on their desktops.  So we shut down the 
server, clear the shared memory and it usually runs fine until the next 
Tuesday.

Any Ideas?

Last Tuesday afternoon we upgrade to 6.5.4FP2.  It ran fine Tuesday 
afternoon and all day Wednesday, then on Thursday morning we started 
getting the same problem again!

Last week we shutdown Websphere and Apache since we don't currently use 
either (leftover projects from an old employee.) So far this morning, we 
have not gotten any insufficient error messages.

We had Websphere and Apache running before with 6 and with 6.5 and no 
problems that I can recall.


Thank You,

Dennis Heinle, MCSA, CLS, A+, Network+
Enterprise Systems Administrator
Guarantee Electrical  "Legendary Innovation" Since 1902
314-773-1111 x139
Dennis.Heinle@xxxxxxxx