[Samba] Samba 3.0.2 mapped by Actve Directory

[Costlow Erik A.]

I have spent a while trying to join a samba machine to our university's
active directory structure so that allowed users can map to it by simply
running \\webserver
I was able to join the machine just fine via: net ads join
VPSA/UH/UH-_ResComp_Servers/ -U adminname
And now I can run wbinfo -u to get a listing of all users on our
network. I have the right permissions, because from that computer, I can
run "smbclient //IP/c\$ -k" and it lets me through as it should.

However, when I run "\\webserver" from any other computer, log.smbd
shows: 
[2004/02/16 10:51:46, 0] auth/auth_util.c:make_server_info_info3(1100)
  make_server_info_info3: pdb_init_sam failed!
[2004/02/16 10:51:46, 2] auth/auth.c:check_ntlm_password(312)
  check_ntlm_password:  Authentication for user [rceacostl] ->
[rceacostl] FAILED with error NT_STATUS_NO_SUCH_USER

How can I make it so users can map their drives to this computer?

Part of /etc/smb.conf
[global]
        workgroup = ADILSTU
        realm = AD.ILSTU.EDU
        security = ADS
        auth methods = winbind, guest, sam
        password server = air.ad.ilstu.edu
        idmap uid = 10000-50000
        winbind gid = 10000-50000
        winbind enum users = yes
        winbind enum groups = yes
        valid users = @AD.ILSTU.EDU\ResCompBackupUser,
@AD.ILSTU.EDU\ResCompAll, @AD.ILSTU.EDU\DevTeam