Problem with CIFS resource

[pch0317 <pch0317@gmail.com>]

Hi,
I use fstab to mount CIFS resource:
/1.2.3.4/my_resource   /mnt/resource   cifs   credentials=/etc/file   0   0

All files which was copied to /mnt/resource have attributes:
rwxrwSrwx

I know, that "S" is when user or group ID is set, but execute bit is 
disable.

My problem is that I can't, for example, extract tar archive on 
/mnt/resource. I think, this is cause by "S".
Whan option during mounting I should use to exchange "S" to "x"

Thanks