Mozilla is going to stop doing an explicit search for Java plugins in Firefox 4 (https://bugzilla.mozilla.org/show_bug.cgi?id=506719)
Java plugin vendors should follow the registry-based solution outlined here:
We need add this registry keys for plugin2. Firefox 4 won't have the old oji plugin support. so there is no need for the oji plugin.
This need be done before firefox 4.0 ships.