I'm using JBoss 4.0.5.
When calling a method on a stateless bean I get:
java.lang.reflect.UndeclaredThrowableException
at $Proxy1.getList(Unknown Source)
...
Caused by: java.lang.ClassNotFoundException: [Ljava.lang.Object;
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at org.jboss.remoting.loading.RemotingClassLoader.loadClass(RemotingClassLoader.java:50)
at org.jboss.remoting.loading.ObjectInputStreamWithClassLoader.resolveClass(ObjectInputStreamWithClassLoader.java:139)
...

The code that causes this:
getHandler().getList(searchCriteria);

getHandler() does a JNDI lookup and returns a remote proxy object.
searchCriteria is of the type List.

The way I see it, the JBoss remoting class loader is trying to load the class for an array, which of course fails. Strangely enough, this problem only occurs with JDK 6.0beta2, and not JDK 5. This definetely looks like a bug, but is it a JDK bug or a JBoss bug? Any thoughts?