Items in SMP appear in wrong location or behind walls

I searched, but could not find if this JIRA was here, it should not be a Dupe. I looked for results with keywords: Drops, Wrong Drops, Item Drops, Items Dropping Wrong, Incorrect Item Drops, ect.

There is a problem with item drops from Mining, Digging, Chopping Trees, Collecting resources, Mobs drops, and ect. To reproduce, do the above mentioned, and items will not always drop in front of you, they end up behind you, around you, or sometimes behind walls, between 1 - 4 blocks thick, and items will drops underground in caves, or above ground if in a cave, if 1 - 4 blocks away. It is irritating, and some items can't be collected because they disappear after a few minutes. This happens in SMP, not tested in SP yet.