With its recent API changes for 1.2, the default serialVersionUID computed for
java.rmi.server.RemoteObject is different from what it was with JDK 1.1, making
it impossible to pass (references to) remote objects between 1.2 and 1.1 VMs.
Such an attempt will fail with a java.io.InvalidClassException with the detail
message "java.rmi.server.RemoteObject: Local class not compatible."

This bug causes a serialization incompatibility in a fundamental type
used to represent RMI remote objects; it introduces a conceptually
trivial, yet unavoidable and completely unnecessary interoperability
failure between RMI applications that talk between 1.1 and 1.2 JDK
versions. It should (and will) be fixed ASAP.

(It does not affect RMI applications that do not require remote
objects from 1.1 and 1.2 VMs to be shared.)