add prev and next links to subpages

Posts are organized chronologically, that’s how those navigation links are possible. In the case of Pages or sub-Pages there is no such common denominator, which means navigation in the same manner is impossible.
However, you may want to use the “child_of” parameter of the wp_list_pages – if the subpages are children of the same Page. This won’t really be a “navigation” but it’s possible to display a list of all the children Pages under a Page.

Found a plugin for the next and previous thing here that I got to work after some fiddling!
http://wordpress.org/support/topic/43071