visual corruption in classic window

Lately, Gnome Do in Natty is experiencing significant visual corruption in its main window as you type. Please note that because this is running in a VM, it is using the classic desktop and only 2D.

The window looks fine when you first summon Do. But then as you type, the background goes black and only the newly typed characters are visible in the small line below the image. Hitting tab and doing other keyboard things sometimes repaints the window correctly and at other times, causes other corruption.

I will attach a screenshot of the window after typing 't' 'e' 'r' 'm' to invoke gnome terminal.

Note that afaict, this is a visual corruption only. In all other respects, Do appears to be working fine. I will test again when the new xorg stack lands for Natty.