I have an Aluminum and a Ti PowerBook with more firewire drives than I can count and I have never had or seen that error before???
in the thread you listed they reference another site, and while its difficult to really understand some of what they posted, and given there is only 2 posts, I would really think there is something else going on that has nothing to do with it
The error seems to appear in the logs of "PowerBook G4 (Titanium)" models, not other models that have the "Titanium" look. 500 and 400-MHz PowerBook G4s only.
I've seen the error in the logs of several of these machines so far, though I have not run into any issues I could empirically link to it.