I didn't see this mentioned in the offical errata document, nor could I find mention of it on the forums.
Sun Certified Programmer and Developer for Java 2 Study Guide (Exam 310-035 and 310-037)
Top of Page 265
switch (x) {
case 2: y = 3;
case 3: y = 17;
case 4: y = 27;
default: assert false; // We're never supposed to get here!
}
The problem is, you will always get there because a lack of break statements will always cause us to fall-through to the default statement.