如何在Java 1.5下的applet中加载JAXB

Exception: javax.xml.bind.JAXBException: Provider com.sun.xml.bind.v2.ContextFactory not found
 - with linked exception: [java.lang.ClassNotFoundException: com.sun.xml.bind.v2.ContextFactory]

javax.xml.bind.JAXBException: Provider com.sun.xml.bind.v2.ContextFactory not found
 - with linked exception: [java.lang.ClassNotFoundException: com.sun.xml.bind.v2.ContextFactory]
     at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:152)
     at javax.xml.bind.ContextFinder.find(ContextFinder.java:299)
     at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:372)
     at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:337)
 .......
Caused by: java.lang.ClassNotFoundException: com.sun.xml.bind.v2.ContextFactory
     at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
     at java.security.AccessController.doPrivileged(Native Method)
     at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
     at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:117)

jc = JAXBContext.newInstance("mypackage", this.getClass().getClassLoader());