Try to register a .CA directly through the eNom panel with accented characters and you get the same problem. This is a huge issue that annoys my customers to no end. Add the fact that you cannot select French as the preferred language for CIRA communications and I consider myself lucky to not have the language police threaten me yet.
If there are ANY accents in the registrant information, whether it's the name, company or address and eNom throws a fit. I wish I would have known this first before I invested too much time and domain transfers into the eNom account.
The best part is, I composed a long letter to eNom support a few months ago to complain and I got the canned response from their support that I should go through WHMCS support. I haven't calmed myself down enough to open a ticket here yet.
My solution for now? Each time I see a failed .CA registration in the WHMCS To-do, I have to go and clean up the mess and re-activate the order, with a good dose of screaming and cursing.