Problems with java

[Marco]

Hi all.
I have a problem with java applets and Firefox. This is the current 
installation on my PC:

- FreeBSD 6.2
- apache 2.2
- tomcat 5.5.17
- firefox 2.0
- diablo-jdk 1.5.0.07.01.
All the packagea have been installed with pkg_add -r (excepted diablo, 
installed with pkg_add from my HD).

When I tried first to execute a very simple java applet, I received an
error message "Missing Plugin - application/x-java-vm".
I followed a suggestion and I created a link like this:
#cd usr/local/lib/browser_plugins
#ln -s /usr/local/jdk1.5.0/jre/plugin/i386/ns7/libjavaplugin_oji.so
After that I haven't received any error message, but, simply, java applets are 
not executed at all, neither my simple trials nor the standard examples for 
java runtime (like TicTacToe and so on).
When I go to "about:plugins" with firefox, I see that java environment is 
active:
--------------------------------------------------
Java(TM) Plug-in diablo-1.5.0-b01

    File name: libjavaplugin_oji.so
    Java(TM) Plug-in 1.5.0

MIME Type 	Description 	Suffixes 	Enabled
application/x-java-vm 	Java 		Yes
application/x-java-applet 	Java 		Yes
application/x-java-applet;version=1.1 	Java 		Yes
application/x-java-applet;version=1.1.1 	Java 		Yes
application/x-java-applet;version=1.1.2 	Java 		Yes
application/x-java-applet;version=1.1.3 	Java 		Yes
application/x-java-applet;version=1.2 	Java 		Yes
application/x-java-applet;version=1.2.1 	Java 		Yes
application/x-java-applet;version=1.2.2 	Java 		Yes
application/x-java-applet;version=1.3 	Java 		Yes
application/x-java-applet;version=1.3.1 	Java 		Yes
application/x-java-applet;version=1.4 	Java 		Yes
application/x-java-applet;version=1.4.1 	Java 		Yes
application/x-java-applet;version=1.4.2 	Java 		Yes
application/x-java-applet;version=1.5 	Java 		Yes
application/x-java-applet;jpi-version=1.5 	Java 		Yes
application/x-java-bean 	Java 		Yes
application/x-java-bean;version=1.1 	Java 		Yes
application/x-java-bean;version=1.1.1 	Java 		Yes
application/x-java-bean;version=1.1.2 	Java 		Yes
application/x-java-bean;version=1.1.3 	Java 		Yes
application/x-java-bean;version=1.2 	Java 		Yes
application/x-java-bean;version=1.2.1 	Java 		Yes
application/x-java-bean;version=1.2.2 	Java 		Yes
application/x-java-bean;version=1.3 	Java 		Yes
application/x-java-bean;version=1.3.1 	Java 		Yes
application/x-java-bean;version=1.4 	Java 		Yes
application/x-java-bean;version=1.4.1 	Java 		Yes
application/x-java-bean;version=1.4.2 	Java 		Yes
application/x-java-bean;version=1.5 	Java 		Yes
application/x-java-bean;jpi-version=1.5 	Java 		Yes
------------------------------------------
The same applets are correctly executed - on the same PC - by konqueror; I 
only had to modify Konqueror configuration changing java interpreter path 
to /usr/local/bin/java.

Firefox in a Windows environment executes correctly all the apples.
Where is my mistake? Where can I find the solution?
Thanks for any help.

Marco