samba - Oct 2003 - Different SAMBA reaction about file permissions

How come am I not able to delete this "aquila_test/toto2" file from
our
"data" (see smb.conf below) directory but can delete it (different
copy but
same permissions and owners/groups) from our "home" (see smb.conf
below)
directory from a "Windows 2000" PC using samba  ( we don`t have this
problem when doing unix commands)

File is on a SUN SunOS 5.8 server

smbd -V
Version 2.0.7

$ ls -ld aquila_test
dr-xrwx---   2 root     vim           96 Oct 29 13:54 aquila_test

$ ls -l aquila_test
total 0
-r-xrw----   1 ab123456 vis            0 Oct 29 11:31 toto.orig
-r-xrw----   1 ab123456 vis            0 Oct 29 11:31 toto2


c0pmtl01 # groups ab123456
vis vim


$ cat smb.conf

#
# Automated Samba config done by dance on Wednesday October 29 12:02:22 EST
2003
#

#
# Global parameters
#

[global]
workgroup = YYY_XXX
server string = C0 File server Montreal Cluster
browseable = No
NIS homedir = No
log file = /opt/VRTSsamba/var/log.%m
max log size = 50
log level = 1
shared mem size = 4096000
security = server
password server = ABCDEF
guest ok = No
dns proxy = No
local master = No
load printers = No
socket options = TCP_NODELAY

#
# Shares parameters
#

#
[home]
comment = MyHome
path = /home/%N/%u
writable = Yes
browseable = No

#
[data]
comment = Data
path = /data/%N
writable = Yes
browseable = No
inherit permissions = Yes

Patrice Lagac?
Mail: Patrice.Lagace@canadair.ca
Tel: (514) 855-5001 #56101
Administrateur de Syst?me
Gestion Globale de l'infrastructure
Transformation d'entreprise et syst?mes
Bombardier A?ronautique