Mozilla has said that the code it uses in Firefox to find the Installed Java will be removed in a future release (at least 4.0, and possibly 3.6).
We used to copy the plugin dll's to the firefox plugins directory (in RegCommon.cpp) but we stoped doing that when firefox startied finding it directly from the default java installation.
we need to:
1.) on install, if installing latest version, copy the appropriate dll(s) to <firefox>/plugins. (and remove dll from previous version)
1.1) on uninstall, remove this dll, and re-copy dll from latest installed version.
2.) In Java Control Panel, when selecting/deselecting "Mozilla Family" copy or remove the appropriate dlls
3.) we also need to consider the same behavior added for chrome (if possible)