File Permission problems FCP and XSAN

We have 5 Mac Pros connected to our XSAN (2 Xserves and 2 Promise arrays.). When a file is created on one of the FCP Macs and saved on the XSAN, the permission are OK (Individual - R/W, Group - R/W & Everyone RO.)

The problem is when a file, generally audio (from our sound booth or music from an outside source) or a graphic (usually Photoshop from our Graphics folks) is brought in over the LAN and save to the XSAN volume, the permissions are Individual - R/W, no group is listed and Everyone - No Access.

If they try work on something that another user started, they get permission errors if the sequence contains a file that was brought in from the outside.

I know we can change permissions on a file, but there are so many of them that it is slowing down production.

Is there anything we can do to either eliminate this happening, or have something like a drop folder they can place a file in to automatically change the file permissions?

Any help with this would be greatly appreciated.

The MacPros are running OS X 10.5.8 and FCP 7.0.3 and the XSAN is running Mac OS X Server 10.5.8 and XSAN 2.2.

Thanks.