-snip-
that doesn't work too well
I could have sworn that used to work.
EDIT: The panoramaScreenShot(name, jpg/png); function works well except you have to use a stitching tool afterward. I haven't used a stitching tool yet, but I imagine there would not be the black border. Regardless, it is a very cool Blockland add-on that will allow you to do this without other programs.