can RDF APIs Draft (SiRPAC) be used in a applet?

I can use the RDF APIs Draft in a java application, howevery, when I adapt it to be a applet to run in Web browser, it seems donesn't work, and during the course of deploying all the package into a .Jar file, it prompt error: SiRPAC class cannot be copied, so I wonder whether the APIs (or it is due to SiRPAC) can be used in a applet?