one editor destroy,another create,combo box can't open

mahuzi wrote:When one editor created in page,you click to open a toolbar combo box ,like font, fontsize etc.
destory the editor,then created another editor,and you click to open a toolbar combo box again,it can't be opend.
and I find this problem in ckeditor demo(sample) too.
demo:http://ckeditor.com/demo
you click a combo box in "Editor with all features" demo.
then you change to "Interface color" demo to click any combo box,it can't he opend.
firebug show some error:
"this.$ is undefined
http://ckeditor.com/apps/ckeditor/3.0.1 ... 1257207309
Line 11"
how to solve it?