Xorg X11 and external output

Hi list, after some (fruitless) attemps to make X11 aware of an external projector, it worked today totaly unexspected. my theory is: depending on the initial state (external,internal,both) X11 get initialised. and this can not be changed afterwards. (atleast for the i810 driver) If there is someone with knowledge about the internal workings of X11, can he perhaps take a look at this anoyance ? (stefan ?) re, walter