I added a new option to Japize to allow excluding svuid information for a particular set of packages or classes. I'm using it on my scripts but I'm mentioning it here because you might want to use it for the runs on Builder too. japize as xxx packages +whatever -whatever -javax.swing:serial That will cause all classes in javax.swing to be emitted without svuids, as if they weren't serializable (although the fact that they implement java.io.Serializable will still be recorded and checked). (I also arranged for enums to get that treatment automatically). Also, any class that *inherits* from a class that's emitted this way will also be emitted without a svuid, because if the superclass isn't serialization-compatible, the subclass pretty much can't be either. Anyone have any particular strong feelings on whether I ought to be specifying the whole javax.swing package or just, eg, subclasses of JComponent? And whether there are any particular bits that should *not* be excluded? (I don't know where to find the Sun documentation that says serialization of Swing isn't supported so I'm not sure exactly what it applies to...) Stuart. -- http://sab39.dev.netreach.com/