[kaffe] Problem with javadoc!help me!

[micc2@libero.it]

Hi! 
I'm a newbie!i have started with java 1 week ago.
when i try to execute javadoc I recive thiss error message:

java.lang.ClassNotFoundException: sun/tools/javadoc/Main
	at java.lang.Class.forName(Class.java:native)
	at java.lang.Class.forName(Class.java:58)

It doesn't find the sun.tools.javadoc.Main.
Have I to set the classpath like this:
javadoc -classpath <dir with tools.jar file:/usr/local...../tools.jar>?
I have tryed but it doesn' work.
Help me please