Mavericks won't log onto Snow Leopard server share points

I have 3 imacs, running mavericks which won't successfully log onto Snow Leopard server share points.

The server appears on the list on the left and i get to a login screen when i select the server.

I enter the username and password and the box just shakes.

However if I tick the "access as administrator" in the user prefs on the server, it can connect, however i don't want certain users to have admin rights.

The strange thing is, is that if i choose to login with a user name and password for one of the older macs (10.6), i can log in. But that defeats the object.

This is obviously an authentication issue between mavericks and SL.

Any one else had this?

Thanks in advance. 🙂