Indeed, spam and flame had been confused. Related terms include "troll" (a person who posts flames in order to instigate a flamefest) and "sock puppet" (an alternate identity of an established poster, often used to perpetuate a flamefest by posing in agreement with the original identity).

More:

http://www.spamfaq.net/terminology.txt

http://www.rahul.net/falk/glossary.html