Oracle Forms

Hi,

I spent the entire sunday trying to "see" a simple javabean working inside Forms... please help me! I followed every step of the Francois Degrelle's tutorial "How to buid a new JavaBean". It didn't work the very first time, i noticed that, entering the Layout editor, forms showed an alert FRM-XXXXX (don't remember the number, maybe 13128) unable to find JavaBean ... I obtained this error to disappear by appending the .jar name to the FORMS_BUILDER_CLASSPATH key on windows registry. Unfortunately in vain (the sample form didn't work still). What's wrong with javabenas? I tried another "classical" bean (the JCalendarJinit, always downloaded from Degrelle's blog) but with no useful results... tried to rebuild all the sources with Jdeveloper and re-deploy the JAR but nothing. The forms compiles fine (no errors, neither in layout editor) and builds but, when running (I used the OC4J web server) the calendar refuse to show is face without any prompt or warning. I'm puzzled... Javabeans seems a very interesting and powerful technology but... how put it at work in Forms?
I'm using: DBMS Oracle 10g XE with Oracle Developer Suite 10.12.02. Can anyone give me any useful hint on this subject?
Thank you for you patience (and my poor english).
Massimo