One of the changes made in the JMX Remote API in Mustang was to add type parameters to the various occurrences of MarshalledObject in the interface RMIConnection (and its implementation RMIConnectionImpl). These interfaces are used internally by the RMI Connector but are not usually referenced directly by user code. The type parameters serve to prevent -Xlint:unchecked warnings and to clarify the protocol implied by the RMIConnection interface but they are not essential.

The problem is that the type parameter to MarshalledObject was only added in Mustang. Its presence in RMIConnection means that that interface can't be compiled or implemented on Tiger. JSR 255 will include this interface in its API, and it is a declared goal of JSR 255 to be implementable on Tiger. So the type parameters must be omitted, reverting to the RMIConnection interface as it was defined in Tiger.