It's not really a bug. It can't push the dropped item out if there's nowhere to push it to.
1.Junk-Jack-Wiki 2. The world is big, 256 blocks high and 768 across. 3. Who is John Galt? 4. Lack of objection does not indicate consent. 5. We scream, we shout, we wail, we cry; but in the end we all must die.