stop xscreensaver from launching on both screens?

[SweWiLLiE]

I've searched for a couple of hours now and found nothing. (everyone else wants the opposite)

I have 2 screens (tft and tv-out).
When I launch xscreensaver-demo it launches the selected screensaver twice (one on my tft, and one on my tv).

Is there a way to stop it from doing that?
I only want it at one display at a time.

[SweWiLLiE]

Noone? This is a bit irritating, trying to watch a nice screensaver (rss for example), instead of looking good at one display, looks crappy on both.