Hmmm, it does seem odd. You should contact them. Did you send by private courier? Coz they ask on the website to use that address if u send that way, i dont know if it makes any difference... dont think it should. But anyway, if i were you i would call them and tell them I haven't received any type of confirmation of receipt for my application and its been over a month now. I don't mean to scare you but i have read in some posts on this forum where some applications were only put in the que after after the applicants would call up cic and inform that several days had passed without any AOR. If you have proof of delivery from your courier then you should provide that to cic and see what they say. But definitely give them a call. I see others who have sent after you have already received their AORs and some of them even approved for SA.
Another thing to keep in mind, i've read in some posts that some applicants who didn't receive an AOR and had no update were sent back their applications due to a missing signature or document. I'm not saying that may be your case but it's just another reason i'm putting out there for you based on what i've read on these forums.
But i hope the best for you.....hopefully it's just laziness in data entry on CPC-M's part.