Impresora Laserjet dice VOTE FOR JOSH

Change the status message of a HP LaserJet printer

by Marc Charbonneau on 22/01/2007 This is an old trick, but always fun. It’s easy to change the status message on a networked HP printer; just telnet to the printer’s IP address on port 9100, and type the following:

@PJL RDYMSG DISPLAY="YOUR MESSAGE HERE"

Press enter, and you’re done; the new status message will stick around until you change it back, or someone restarts the printer.

http://blog.mbcharbonneau.com/2007/01/22/change-the-status-message-of-a-hp-laserjet-printer/

This April 1st, Someone logged into the printers and changed the ready screen to "vote for josh" on numerous hp laserjet printers. Know that they must have logged in via telnet. And I found this article about how to perpatrate this activity: http://blog.mbcharbonneau.com/2007/01/22/change-the-status-message-of-a-hp-laserjet-printer/ I am just wondering, how can i figure out who has done this mischief? Does HP telnet on printers keep an access log? if so, how can i access it?
UPDATE: My question is not how to prevent this attack. I have since disabled telnet config, and put a password on the admin interface. my Question is whether there is a log of IP/host addresses, or any other log i can review for more information about where this came from.