Objects occupy the same space when keyframed

I have a problem which I cannot seem to find any documentation online. In my scene I have a a set and in the set are three different types of items, bricks, cinder blocks, and pieces of pipe. I duplicated each so that I have maybe twenty or thirty of each and placed them randomly around the scene so the physics will drop them in a natural way. However, when I set a key frame on them, or when I render their game physics to IPO, each of the bricks occupy the same space, each of the blocks occupy the same space, and each of the pipes occupy the same space. The result is an explosion. This is not what I want.

They do not occupy the same space before they are keyed but instantly do afterwards. The IPO curves are cleared before the animation is done yet as soon as I set a location key, they all key to the same spot. Please help.

You need to delete the datablock in the IPO editor for each object. When you duplicate it also duplicates any location keyframes so you need to make them al single users, having individual keyframes IPOs
The datablock concept is useful to understand to overcome these problems not just with animations http://wiki.blender.org/index.php/Doc:Manual/Data_System/Datablocks

That’s different then removing all of the values from the NLA editor then?

If they have the same datablock in the IPO editor for each individual object you’ll have to delete them.

that worked. Thanks a lot.