I use the JRE (build 1.6.0_18-b07).When I launch the application with the Firefox tells me I need plugins??>
I know this is seriously old. But we ran into this issue a while back and adding the line you mention....
will not allow firefox to access your forms application.
you need to remove the last part of the value to have it work correctly.
This has worked for us on 10.1.2.3 forms as well as 11.1.2
to enforce the java version, you need to add a few more lines
you also need to add java_version="%java_version%" to your base.htm and xxxjpi.htm web files.