Named streams are used to store Mac OS X extended attributes and can be leveraged to avoid using AppleDoublefiles to store the data fork and the resource fork of legacy Mac files.
Mac OS X Server v10.5 and v10.6, as well as many Network Attached Storage (NAS) devices, support named streams when you connect to them via SMB.
Microsoft Windows servers with NTFS-formatted hard drives also support named streams when you connect to them via SMB; named streams are called “Alternate Data Streams” in Windows.
Mac OS X v10.5 and v10.6 clients automatically enable named streams support when they have a SMB connection to a Mac OS X Server v10.5 or v10.6-based server.
Mac OS X v10.6 clients automatically enable named streams over SMB when the NAS or Windows server claims to support it. See below for details about how to activate Mac OS X v10.5 client support of named streams over SMB connections to a NAS or Windows server.
open up the Terminal Command Line Utility found under Applications > Utilities then do the following commands.
1) su root
2) [use the root password you just created]
3) cd /etc
4) touch nsmb.conf
5) emacs nsmb.conf
6) [Copy and Paste the following]
7) Control X > Control S > Control X > Control C
8) Exit Terminal and Reboot the Computer.
When you’ve completed this and the computer starts back up it will refresh the networks settings and find this file and force NTSF streams when connecting to other servers.
More Details at Apple Support