Both JRE 1.4 and JRE 1.5 are supported on the client browser for TS 6.7.1 SP1.--Michael
JVM 1.4 still works with 6.7.1 but most of the functionalities of Launchpad will not work as desired. Ex.. Your launchpad settings will be lost and you have to set everytime you try to edit files :-)
All client computers require a Java Runtime engine, such as Sun JVM 1.5(downloadable from www.java.sun.com) or Microsoft JVM.