Hiding Menu items for which there is no content

I am developing a site which uses the "Content Access" module.

If I create a 'menu link' on the edit page of a node, the menu link is diplayed only if the user has sufficient rights to view the node (this is the behaviour I want).

If I create another node and another menu link of the same name (in an attempt to put two nodes under the same menu link), this fails as I get two menu links, identical in title but displaying two different nodes.

If I create taxonomy terms and then a corresponding menu to show the nodes possessing those terms it works fine - expect that the menu link is displayed even when there is no content that the user has rights to see.

Is there a way I can hide menu items that have no viewable content for the user in question?

Cheers,

Martin.