From http://star-wip.sfbay.sun.com:88/en/download/manual.jsp,
Click on Instructions of Linux X64 and Linux X64 RPM link to:
http://star-wip.sfbay.sun.com:88/en/download/help/5000011400.xml
http://star-wip.sfbay.sun.com:88/en/download/help/5000011300.xml

These pages need to be updated with proper Linux version. They still have RH2.1, RH3, etc.

6u21 supported platforms: http://java.sun.com/javase/6/webnotes/install/system-configurations.html