I can't seem to find a better place to point out bugs in the tutorial, so I hope someone here knows what to do with them :-)
I found a few small errors in the 1.3.0 tutorial:
On page 8/9 a new SessionBean is created. On page 8 are the old instructions for the 1.2.x series, on page 9 are the correct instructions (including screen shot) for 1.3.0. The old instructions should be removed, I think.
On page 11 the method body for the compute(int) method is given. Its return type, however, is void[], which should be double[].