[Samba] 3.0.1pre1 broke my 'valid users' on one share

[Aaron_Colichia at Dell.com]

Before updating to 3.0.1pre1, the following smb.conf worked.
 
Now when users try to hit the [broke] share they are denied access.
 
Winbind has no problem finding the users and groups for the domain.
 
I've verified filesystem permissions, "Domain Users" have full RW access.
 
I do not seeing anything coming across my smbd log files.
[global]

security = DOMAIN

workgroup = xxx

password server = AUSTIN, HOUSTON, *

encrypt passwords = yes

wins server = 172.20.0.1

netbios name = PLANO

winbind separator = + 

idmap uid = 10000-20000

idmap gid = 10000-20000

winbind use default domain = yes

winbind enum users = yes

winbind enum groups = yes

obey pam restrictions = yes

kernel oplocks = no

template homedir = /xxx/home/share/%U

template shell = /bin/bash

server string = 

mangle case = yes

dos filemode = yes

name resolve order = wins bcast lmhosts 

socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192 SO_KEEPALIVE
IPTOS_LOWDELAY

max log size = 4096

log file = /var/log/samba/%m

local master = yes

domain logons = no

domain master = no

preferred master = no

wins support = no

wins proxy = no

dns proxy = no 

[broke]

write cache size = 64000

browseable = yes

path = /path/to/stuff

read only = yes

public = no

guest ok = no

valid users = user1, user2, user3

force group = "Domain Users"

fake oplocks = yes