Debugged the verification of the validity proof. Found a way to make it work:

Changed the Abstract Element equivalence method...
It now uses getBigInteger.


@Rolf: Please revisit that code
(Also check for equals!)

@All: A new example provided by Jürg Ritter has been inserted: ValidityElGamalSerialization and Deserialization. This way the test runs over multiple JVM-instances.