Apple Computer acknowledged the problem late on Monday and posted a workaround to its Web site.
"After updating to Mac OS X 10.3.9, some systems may have issues with Java applications and Java-enabled websites when using Safari," the Mac maker said in a posting to its support Web site. "Safari may unexpectedly quit, and standalone Java applications may unexpectedly quit or not launch."
An Apple representative said the company plans to keep the update available. As of 5 p.m. Monday, it had not posted information alerting customers to the potential Java problem on the download page for the update. Apple released the OS update on Friday.
Among those hit by the bug were David Geller, CEO of Seattle-based e-mail marketing company WhatCounts, who said it affected both his 15-inch PowerBook and a dual-processor Power Mac G5.
"I found my entire Java development toolset stopped working right after applying 10.3.9," he said in an e-mail interview. Geller said he wondered how such "an egregious error" slipped through Apple's testing.
"I sure hope Tiger is better than this release," he said, referring to the next major update to Mac OS X, which is set to. "I really want to love this stuff, but (Apple is) testing my patience, especially since I've moved all my developers to OS X."
For those who are affected, Apple said the problem can be fixed by reinstalling two earlier security patches: Java 1.4.2 Update 2 and Security Update 2005-002.
The Cupertino, Calif.-based company also offered up a test that people can do to see if their systems are affected. Customers should open the terminal program and type "java -version" (without quotes) and then hit return, it said. Computers affected by the issue will get the message "Segmentation fault."