>> All changes I tried (increasing data segment and stack size,
    >> other Netscape versions (Linux)) failed :-(.

    Jason> ...in csh, you can:

    Jason> 	unlimit datasize <- affects brk(2) unlimit memoryuse
    Jason> <- affects mmap(2)

    Jason> ...as I recall... you might try the latter if you haven't,
    Jason> yet.

Maybe I'missing something, here are more data of my environment:

After setting 'datasize' and 'memoryuse' to unlimited I see under csh:

% limit -h
cputime         unlimited
filesize        unlimited
datasize        1048576 kbytes
stacksize       32768 kbytes
coredumpsize    unlimited
memoryuse       43976 kbytes
memorylocked    43976 kbytes
maxproc         unlimited
openfiles       unlimited


% limit
cputime         unlimited
filesize        unlimited
datasize        1048576 kbytes
stacksize       2048 kbytes
coredumpsize    unlimited
memoryuse       43976 kbytes
memorylocked    14658 kbytes
maxproc         80 
openfiles       64 

>From that point I started netscape and tried to send a mail in the
Outbox (It's easier than writing always new dummy ;-)). Result (as
ever :-():

An error occurred delivering deferred mail.

Netscape is out of memory.

Try quitting some other applications or closing some windows.
---------------------------------------------------------------------

'top' displays:

load averages:  2.00,  1.77,  1.54                                     07:42:01
42 processes:  4 running, 38 sleeping
CPU states: 51.2% user,  0.0% nice, 48.8% system,  0.0% interrupt,  0.0% idle
Memory: 17M Act 6676K Inact 4968K Wired 17M Free 14% Swap

  PID USERNAME PRI NICE   SIZE   RES STATE   TIME   WCPU    CPU COMMAND
17002 kilbi    105    0  6800K 4844K run     3:09 98.49% 98.49% netscape
16954 root       2    0  1468K 1528K sleep   0:33  0.05%  0.05% sshd
  145 root      18  -12   348K  432K sleep   0:25  0.00%  0.00% xntpd
  136 root      18    0   256K  276K sleep   0:02  0.00%  0.00% cron

On /tmp, /usr/tmp is enough space left (I hope: Several MB's).

Further suggestions?

Markus.