Medium-Major Bug: Rite of the Wolf Giver starts even if you aren't a werewolf and did not advance the main BM quest.

Title is self-explanatory. You can find the rumour lying next to the Argonian shipmaster that starts this quest (http://www.uesp.net/wiki/Bloodmoon:Rite_of_the_Wolf_Giver) even before you're infected with lycantropy and even if you haven't advanced the main BM quest at all.