#11 DatabaseDifferences works only once

[Kees Schotanus]

demo/jsp/dmc/DatabaseDifferences.jsp works only once.
When the Database differences tree item is clicked for a
second time, the next exception is thrown:
java.lang.NullPointerException at
java.lang.Class.forName0(Native Method) at
java.lang.Class.forName(Class.java:141) at
org.jxpfw.demo.jsp.dmc.DatabaseDifferencesJSPBean.pro
cessSubsequentPass
(DatabaseDifferencesJSPBean.java:310) at