Sue Walsh over at IGotSpam (one of the CW blogs I occasionally write for) notes that another "worm" has hit Nokia phones. From the list, it appears she is talking about S60 2nd Edition handsets and not ones based on the more recent, more secure, S60 3rd Edition.
This is a problem for any highly successful device or computer manufacturer: people will continue to use the devices well past their expiration date. They may not know--or even care--about "flaws" like these worms. Even though Nokia has addressed the issue going forward, there's little that can be done for those legacy handsets other than replacement. Hopefully that will happen over time.