Saft and Acid Search both appear to break. Be sure to contact their developers for update. Saft 7.7.1 is reported to solve the problem people have with Saft. If the installer unexpectedly quits in the middle, run the combined update over again

http://www.apple.com/support/downloads/macosxcombinedupdate1039.html

Note, my combined updater first reported the update was incomplete and recommended to me to apply it over again. Even if your update does not, it is recommended if the update does not finish.

And if you didn't apply the March Security update, apply it since that will fix many a Safari crash with Java.

http://www.apple.com/support/downloads/securityupdate2005003client.html

In addition, you should know these tips before applying any update on an Apple:

http://www.macmaps.com/upgradefaq.html

All went well on an iMac G5 1.7 Ghz with 2 GB of RAM and 37 GB free hard disk space.