Steps to reproduce:

http://zkfiddle.org/sample/102lnsb/1-Listbox-bug-Zk-8-0-4-2-Scroll-bug-after-sort-with-ROD

Scroll down with mouse untill 4-5 row needs to be rendered by ROD. Wait for the render, then sort by any column.

The problem:
A large white space will be between the headers and the first row.

I created a GIF animation from the problem.