The only polearms that can be swung from horse back are the hafted blades now, I believe, a while back staves were swingable and could couch, no more, anyway, I'm pretty sure there was a stickied thread on this somewhere on the forums. It tells every attack/special properties of all weapons in c-RPG. Do a search on "heirlooms" or "weapons", if you look I'm sure you'll find it.