As already notices in an earlier post, there is nothing to forbid online harassment to fall within the current legal definition of definition. Harassment traditionally involves repeated behaviours or course of conduct in terms of speech or physical actions which causes distress, the victim feeling harassed. Whether one uses a fake identity or not is no obstacle to acknowledge liability as long as the mens rea is there.
That mechanisms to report abuse also exist is the least that can be done...
"What's The Goal Of Anti-Cyberbullying Moves?" (TechDirt, 19 December 2008)
"Missouri Prosecutors Going Overboard In Bringing Cyberbullying Cases" (TechDirt, 22 December 2008) and on the legislation previously passed, "Missouri Makes Online Harassment A Felony" (TechDirt, 2 July 2008)
"Reporting Bullies Online: Helpful Or Not?" (TechDirt, 15 October 2008)
For an example which escaladated to criminal damage and fear of violence, see the chinese online version of mobbing... "Man Wins Lawsuit Against Online Vigilante Mob In China" (TechDirt, 22 December 2008)
But for misuse of legislation... "How Is It Cyberbullying When Students Are Exposing Teacher Abuses?" (TechDirt, 31 December 2008)