This is a mirror of the tip on Apple Support Communities, from the author. Links on this page may give me compensation.
Those without Firewire as shown below:
but with USB is necessary to get the latest Java found on one of these two links after upgrading to 10.3.9:
http://support.apple.com/downloads/Java_Update_for_Mac_OS_X_10_3_9
Java for Mac OS X 10.3 Update 5
Those with Firewire should at least consider updating to 10.4.11 to get a later Java, as is described in this tip:
https://discussions.apple.com/docs/DOC-6492
Those with G3 processors able to be upgraded to Mac OS X, but no USB ports built-in, may update to 10.2.8, and use this update page to find their update:
Mac OS X 10.2: Chart of available Mac OS X 10.2 software updates
Note some of these updates may be difficult to find, and might need searching as described here:
Knowledgebase links of the info.apple.com format no longer work