What does a green icon mean and why do the package bodies not expand when they have it? In SQLDeveloper 4 some 10g PL/SQL packages have a regular crate while others have a green dot.

Those with the green dot do not expand their bodies (might be just a coincidence). What is the difference between the packages with and w/o a green dot and why do some packages not expand their bodies?
The green bug you're seeing (look closely) means the package have been compiled with DEBUG option. It is also seen on bare procedures and functions. It is a coincidence they don't expand - maybe a bug (duh) in SQLdeveloper :) On mine, these expand without problem.