[Wine] Shearing in screenshots of DirectX?

[IBBoard]

I'm trying to take screenshots of the Dawn of War game through Wine. The game runs fine and under Windows it has a built-in screenshot function that dumps a JPEG to  a sub-folder. 

Under Wine the game never gets the print screen request because Compiz or Metacity hijack the signal first and start Gnome-Screenshot. Sometimes the screenshot is okay, but other times the screenshot has shearing/artifacting it in, presumably because the trooper in the game moved before the screenshot app could copy the whole image buffer.

If I change the key bindings so that nothing is intercepting the print screen then I do get a screenshot in the folder as expected, but it is pure black and so isn't very useful.

Is there any way to get screenshots from DirectX games under Wine that doesn't involve repeatedly taking the screenshot until I get one without shearing?

If it makes a difference I've got a Radeon X800XL with the latest official FGLRX drivers installed and I'm running 0.9.56 from the Fedora repos on F8.

Thanks.