'%u' is samba specific. Although you would probably be able to use '\\server\%username%' (This would use the windows username).
That is, \\server\%%username% or, in a batch file, \\server\%%%username% Tricky buggers, those %'s :)
-- To unsubscribe from this list go to the following URL and read the instructions: http://lists.samba.org/mailman/listinfo/samba