vB4 Where is this and how to remove?
 

Whilst modifying a vBulletin 4 theme we've come to a stop. This white line, border or margin... whatever is causing it, is from the default vBulletin 4 theme. Looking over stylevars and CSS I am stumped. It's in forum display between threads.

http://i49.tinypic.com/2qdc4dt.gif

Highlighted in red, what is it and how do I remove/modify it.

Cheers.