1. A method for loading a first version of a class into a second version of a runtime environment running a second version of the class, the method comprising the computer implemented steps of: instantiating an object in a first version of a runtime environment wherein the object is an instance of a first version of a class loaded in a first version of a class loader; serializing the object to create a serialized object and storing the serialized object on a storage medium; allowing the first version of the class to be modified to create a second version of the class, wherein the second version of the class has a different definition from the first version of the class; loading a second version of the class in a second version of a class loader for a second version of the runtime environment; receiving the serialized object in the second version of the runtime environment, wherein the first version of the class is incompatible with the second version of the class loader for the second version of the runtime environment; constructing a class file with a class file name for the class that represents the serialized object and a serial version identifier for the first version of the class; loading, into the second version of the runtime environment, the serialized object using the class file as constructed in an auxiliary class loader compatible with the first version of the class; and converting information from the serialized object into an intermediate storage format for use with the second version of the runtime environment.