[Samba] Win XP Pro, Samba 2.2.5, Sybase ASA and Linux 2.2.19

[Gregory J. Neumann]

Greetings, all!
Samba has served me well these past 4 years.  Now I have encountered problems.  I 
hope somebody can give me some insight:
Server: custom-compiled Linux 2.2.19
    Dual P-III 1000
    512 Meg ECC RAM  (never touch the swap partitions!)
    Dual 9 gig Ultra-SCSI drives
    Software RAID level 1 for the Samba share partition.
    Sybase ASA v. 7.0.3.2047 for Linux running on the server to provide database 
services for a Windows business app.
    Samba v. 2.0.7, updated to 2.2.5 to try to fix things.
Problems have started to occur when we changed to WinXP Pro for 5 of the 10 
Workstations.  The Windows app that uses Sybase has started to crash predictably on 
the WinXP machines.  The Win98 machines are less affected, but seem to be more 
error prone.  Sybase has NOT crashed once, it runs on the Linux side and seems 
totally unaffected.  I've changed the settings to be very promiscuous, as this is a small, 
trusted LAN isolated from the internet, but nothing seems to help this.  The software 
vendor is blaming Samba/Linux.  The errors are mostly "kernel32.dll" related, it usually 
occurs as information is saved and a print job is generated.  NONE of the printers are 
handled by the samba share, they work from an Intel Netport server.  I thought maybe 
the program needed to run as "administrator", though the vendor says it doesn't, that 
didn't change this particular problem.  Has anybody seen anything like this? 
Some pertinent smb.conf settings:
null passwords = true (hold over from DOS programs)
security = user
encrypt passwords = yes
update encrypted = no
socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
load printers = no
os level = 65
preferred master = yes
local master = yes
preferred master = yes
wins support = yes
 [SHARE]
       path = /raid/smbapp
       valid users = joe bob mary @samba
       write list = joe bob mary @samba
       writeable = yes
       create mask = 0660
       directory mask = 0775
       guest ok = yes

If you can just give me a clue as to where to start, I don't mind reading, and "testparm" 
is a wonderful tool!
Thanks In Advance!
Greg Neumann