Well, I have my own core and I had people ask me if I cna fix there BG que problem, so I made a patch and now its being put into Arcemu next Release:
Here is a link to were to download it:
dxdemu - Revision 1: /Scripts and Fixes/Arcemu/Battlegroundfix
Its in a SVN. You need tortise SVN, if you need help inserting the patch, Message me.