I have two machines that I do remote logging with. On one of them, I upgraded to 10.2.5 with the smaller updater and had no problem.
Then I heard that there were problems for some people, so on my primary machine, I used the 10.2.5 Combo Updater. That broke remote logging, just like going to 10.2.4 did. So, I point you to the same hint and fix as last time...
Mac OS X Hints
http://hints.macworld.com/article.php?story=20030415094059703