On virtual machines and expected behaviour

Ever tried running this on your ENTERPRISE VIRTUAL MACHINE?
Integer a = 1000;
 Integer b = 1000;
 System.out.println("a == b (1000 == 1000): " + (a == b));

 Integer aa = 100;
 Integer bb = 100;
 System.out.println("aa == bb (100 == 100): " + (aa == bb));
Guess what's the output, run it and report back.

>>42
Well, you almost had me for a minute there but I was looking at the older version of the spec. Compare:
http://java.sun.com/docs/books/jls/second_edition/html/lexical.doc.html#101083
http://java.sun.com/docs/books/jls/third_edition/html/lexical.html#3.10.5

And note the careful rewording of:
"Strings computed at run time are newly created and therefore distinct. "
into:
"Strings computed by concatenation at run time are newly created and therefore distinct. "