[plt-scheme] drscheme vertical split?

Hi,

Sorry for such a mundane question, but I can't find a way to split the window vertically in DrScheme (4.2.5). 
Is it possible? (the split option in the view menu seems to be horizontal only)

With wide screens (quite standard these days), splitting vertically is quite useful. 

An alternative is to just open two windows, but then I can't seem to have two windows open on the same file. Even if I explicitly drag the file I'm already seeing in window1 into window2, I just get a refresh of window1, and nothing in window2.

Any idea?

Thanks!

-- Éric