Based on what you've posted my best estimate of what's happening is that
the users in question are launch the TSM Web Client (not the Web Admin)
which requires a Java 2 plug-in.  Once the plug-in is downloaded and
installed there are likely some older Java applets that don't work with
the plug-in.  Case in point is the command line applet in the Web Admin.
So to switch between the two you have to alter the browser settings so do
de-select the Java 2 plug-in when you want to run an applet that does not
like Java 2.

Regards,

Mike Dile
Tivoli Storage Manager Client Development
Tivoli Software, IBM Software Group
mikedile AT us.ibm DOT com