i use debian stabe for fileserver. there are many files and ~30 client. i have 
some xls, which made reboot the server if i try to open them from a windows 98 
client. from w2k is ok.

some log:
---
[2003/11/10 12:51:53, 5, pid=304, effective(1003, 101), real(0, 0)] 
lib/util.c:show_msg(286)
  smb_vwv[0]=255 (0xFF)
[2003/11/10 12:51:53, 5, pid=304, effective(1003, 101), real(0, 0)] 
lib/util.c:show_msg(286)
  smb_vwv[1]=0 (0x0)
[2003/11/10 12:51:53, 5, pid=304, effective(1003, 101), real(0, 0)] 
lib/util.c:show_msg(286)
  smb_vwv[2]=2 (0x2)
[2003/11/10 12:51:53, 5, pid=304, effective(1003, 101), real(0, 0)] 
lib/util.c:show_msg(286)
  smb_vwv[3]=1 (0x1)
[2003/11/10 12:51:53, 5, pid=304, effective(1003, 101), real(0, 0)] 
lib/util.c:show_msg(291)
  smb_bcc=16
[2003/11/10 12:51:53, 3, pid=304, effective(1003, 101), real(0, 0)] 
smbd/process.c:switch_message(667)
  switch message SMBtconX (pid 304)
[2003/11/10 12:51:53, 3, pid=304, effective(1003, 101), real(0, 0)] 
smbd/sec_ctx.c:set_sec_ctx(314)
  setting sec ctx (0, 0) - sec_ctx_stack_ndx = 0
[2003/11/10 12:51:53, 5, pid=304, effective(0, 0), real(0, 0)] 
smbd/uid.c:change_to_root_user(216)
  change_to_root_user: now uid=(0,0) gid=(0,0)
[2003/11/10 12:51:53, 4, pid=304, effective(0, 0), real(0, 0)] 
smbd/reply.c:reply_tcon_and_X(335)
  Got device type IPC
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/password.c:authorise_login(745)
  authorise_login: ACCEPTED: validated uid ok as non-guest (user=mazsola)
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/service.c:make_connection(488)
  Connect path is /tmp
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/sec_ctx.c:push_sec_ctx(282)
  push_sec_ctx(0, 0) : sec_ctx_stack_ndx = 1
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/uid.c:push_conn_ctx(285)
  push_conn_ctx(0) : conn_ctx_stack_ndx = 0
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/sec_ctx.c:set_sec_ctx(314)
  setting sec ctx (0, 0) - sec_ctx_stack_ndx = 1
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/sec_ctx.c:get_current_groups(162)
  get_current_groups: user is in 4 groups: 1003, 101, 1031, 1042
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/sec_ctx.c:pop_sec_ctx(421)
  pop_sec_ctx (0, 0) - sec_ctx_stack_ndx = 0
[2003/11/10 12:51:53, 3, pid=304, effective(0, 0), real(0, 0)] 
smbd/sec_ctx.c:get_current_groups(162)
  get_current_groups: user is in 4 groups: 1003, 101, 1031, 1042
[2003/11/10 12:51:53, 5, pid=304, effective(0, 0), real(0, 0)] 
smbd/connection.c:claim_connection(156)
  claiming IPC$ 0
[2003/11/10 12:51:53, 5, pid=304, effective(0, 0), real(0, 0)] 
smbd/password.c:create_nt_token(255)
  user token sid S-1-5-21-1428986172-1785154849-1033180803-3006

---

and here the server reboot.
i changed kernel (2.4.17, 18, 22) 
fs is ext3.

any idea? what should i more write?