If your database is on the same server as the webserver that served the applet, and you use that same servername/ip address in the connect string, signing the applet is not strictly required. In other cases, it is.
If you follow the instructions in the document, it works.
On the Oracle TechNet site, in the jdbc driver download section, you can find a download called demo.zip. It contains a complete applet / thin driver example.
Regards, Jan [ May 09, 2007: Message edited by: Jan Cumps ]