http://www.cites.org/eng/resols/11/11_10.shtml
I always though Live Rock was listed as Appendix I. I can't find any concrete reference other than the above though. I'm pretty sure it is.
If you're really unsure, ask Canada Customs. Their database does list "Live Rock" as an import category if I am not mistaken. You just need to get ahold of someone who actually knows (you've probably just get a run-around if you've been trying to call people).
I wouldn't attempt to bring rock across the border without valid documentation. If customs does beleive you to be in violation of CITES, it is serious business from what I've been told. Big time fines, possibly even jail time. I'm not sure but that's what I've been told. It's not worth the risk.
[ 30 May 2002, 18:50: Message edited by: delphinus ]