Java Plug-in should provides users an option to choose
a) Ability to configure Java Plug-in Cache settings remotely. Network administrators find it hard to configure for hundred of users in a company environment.
b) Enable/Disable deleting Java cache from the system similar on the line of Internet Explorer (Tools - Internet Options -> Temporary Internet Files -> Settings).
c) Default limit set on Java's cache size. Present default setting "Unlimited" is not proper.

For details, see this incident at:
http://webbugs.sfbay/rt/incidentDisplay?incidentID=503907