Proxy Pivot Problem

[Devin Johnston]

I've made a patch of grass, it's made up of hundreds of small plane objects that were scattered around randomly. As usual when I make my proxy I collapse one of the objects and then attach all of the other objects to it making one editable mesh. Then I make sure to move my pivot point to the center of the object and then I export. The problem I'm having is once I export the mesh and it converts to a proxy the pivot point changes. It's no longer centered on the object and all of the axis have rotated so that when the object is scattered it doesen't lay flat on the surface becuase the center is wrong. I can move the pivot point back to the center bottom of the proxy but if I try to reorient the axis so that they are all at 90 degree angels it turns the proxy it's self. I've never seen this before, does anyone know how to fix this so the center is properley located?