Why cant I get the previewed result in high render quality???
And why are there still those jagged shaddows??????
Somebody promised me, that this problem would be solved in 2.0.
Make sure that sharp shadows are checked when creating the final rendering. Also, you may want to increase the global illumination quality.
Alternatively you may want to switch to the realtime render mode for the final rendering and set a time to let the image finish.