Yes, what Guys_Fraser said: the problem is that one (the right one) is defined: the extra sidebar.
After choosing a 3-column design (doesn’t matter if it 2 sidebars left or sb-content-sb etc), the right sidebar is already fixed (the Extra-for 3 column pages sidebar).
You can only choose which sidebar you want as a left sidebar, as there is only one option for a sidebar.
This is very limiting, as mostly I want the right sidebar often to be different on 3-column pages and the left sidebar for certain categories etc as well. We need two choice options when using a 3-column page, else the entire 3-column set up is useless as it has no flexibility..
Thanks!
