[OS X Emacs] tabs

[Tom Van Vleck]

tabs are much improved in aquamacs 1.6,
but some behavior surprised me.

I did this:
(obof mode off, show tabs on)
open four files, each with a tab on the tab bar.
C-x-2 to split the current window
C-x-f anotherfile to open a 5th file in the upper pane. the 5th file  
gets a new tab.
C-x-0

The tab bar vanished, and the file that was in the bottom pane
is now the only file in the application window.
The Window menu still shows the other files.
Selecting them will cause tabs to return one by one.

This is not what i expected.. I thought it would
return to the state before splitting, except that the tab bar would  
have 5 tabs.

(also, is there a way to rearrange the tabs?
the intuitive approach, of dragging a tab, does nothing.)