[jitter] built-in isight non-auto exposure ?

hello,
just wanted yo know if anybody is aware of a possibility to turn off  
the auto exposure (shutter)
of the built-in isight (macbook OSX).
googeling only brought up iglasses to me.
http://www.ecamm.com/mac/iglasses/mod.html
which does what i want, but unfortunately it is application-depended  
and max/jitter is not on its list.

best
klaus