If you change the sort on a collaboration system, it does not seem to change which threads the next and previous buttons link to when you are viewing a thread. So, if you click on a thread in the list when the collab is sorted by title, you're taken to that thread, but if you click on Next when you are viewing that thread, you are taken to some other thread, not the one that is next in the collab list.

An example is at

http://demo.plainblack.com/demo1179957877_690/home/my-collab 

Click on the second thread. Then click next. It takes you to the last thread on the collab's list (on page 2).

Susan B