Samba create mask and dir mask on RHEL 4.8

Hi Experts,

I'm using samba -3.6.1 on Red Hat Enterprise Linux ES release 4 (Nahant Update 8) ,all seems ok. The issue im facing is as follows.

When ever a user creates a file via windows explorer the permissions assgined to the file are as follows

-rw-rwxr--+ 1 tom group2    0 Mar  9 10:02 testfile

drwxrwsr-x+ 2 bob group1 4096 Mar  9 10:38 testdir

Im ok with the directory permissions but would like the file permissions to be 644, following are my smb.conf ( create mask ) details

create mask = 0644
        force create mode = 0644
        security mask = 0664
        force security mode = 0664
        directory mask = 2775
        force directory mode = 2775
        directory security mask = 2775
        force directory security mode = 2775

Also I have Linux ACL's on the shares for as the requirement called for some complexity so that only a few users in a group have access to the share.Could you experts help me with suitable mask that i need to use in smb,conf and a little explanation would be appreciated.

Thanks in advance

Sorry for interrupting I'm also looking for mapping the windows drive from linux server.
I will be very happy if i get the steps to configure this.Please help me in this.

windows server 2003.
Linux details:-
[oracle@testdb ~]$ tail /etc/redhat-release
Red Hat Enterprise Linux ES release 4 (Nahant Update 5)
[oracle@testdb ~]$ cat /etc/issue
Red Hat Enterprise Linux ES release 4 (Nahant Update 5)
Kernel \r on an \m

[oracle@testdb ~]$

Thank you.