Netscape did not fully support Java 1.1 until version 4.06 of Netscape Communicator and Netscape Navigator. While the SiteSurfer applet will run acceptably in Navigator 4.0 through 4.05, you may experience some bugs. We therefore recommend if you are running version 4.05 or earlier that you upgrade to Navigator 4.06 or higher. Navigator 4.06 and higher offer superior Java 1.1 implementations on Windows 95, Windows 98 and Windows NT.
Download information is available in Where to Get Java.