Mac files lose their identity

We’re in the process of moving over to a Win2000 server from Novell servers. Both Mac users and PC users store files on the Novell server. It appears that when we copy Mac files from the Novell server to the Win2000 server they lose their identity. In other words, they show only as being PC files and lose any association with applications. Any ideas on why this is happening or how to prevent it? I have to admit I haven’t noticed if the same is true with PC files.