Any solutions for shared storage?

Hello,

I currently have a Windows 2003 server and a NAS running Win2k SBS. Of course, in a workgroup environment

My clients need to authenticate to the server through a client and then be able to write to the NAS.
So far I have been unable to get this configuration to work. The client is not able to write to the NAS. Does anyone have any suggestions on how I can get around this?
Is DFS an option?