Ubiquity panel "truncated" in Minefield, Windows XP

When opening the Ubiquity panel with Ctrl+Space, the panel that opens up is "cut off" at the bottom. It extends from the top edge of the browser window right up to to the top edge of the page area. The rest of it is truncated. It is still usable, but a lot of information is just not displayed. It is as if the page area had a higher "z-index" than the panel - since the entire Firefox interface is styled with CSS, that might be the cause of the problem.

This happens independently of what skin I use.
I am using the Minefield trunk and Ubiquity 0.1.3. Build ID: "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2a1pre) Gecko/20090104 Minefield/3.2a1pre Ubiquity/0.1.3"

I'll try upgrading to a development version of Ubiquity next, in case that fixes the problem.

I would post a screenshot, but the Ubiquity panel eludes my attempts at capturing it with Prnt.