i use something like
pointObj oCenter = new pointObj(oMap.getWidth()/2,oMap.getHeight
()/2,0);
oMap.zoomScale(scale, oCenter, oMap.getWidth(), oMap.getHeight
(),
oMap.getExtent(), oMap.getExtent())
where "scale" s is in fact the 1/s scale you are targetting. eg for 1/20000,
scale = 20000
cheers,
tb
