I don't see this as a back-meta question. Assuming your client is smart
enough to eat it, why not just search under base o=foo, scope sub, filter
(|(id=100)(personid=100)(pid=100))?
The back-meta question might be something along the lines of rewriting
attribute names, but it's not clear whether or not you have a hard-minded
client that would require such a thing. If this is what you're interested
in, I recall this as discussed previously on the list; search the
archives.