Comments from Srinivas Mandalika on the bug:

In the sanity test with BeanBuilder for bug 4927589 is throwing an exception while saving a Frame, which is different from what is documented in the BeanBuilder Docs.However the exception is occuring in the b51 also. So it is not a regression.

4972589 Undocumented javax classes in dt.jar
Following are the steps to reproduce this
Downloaded and install BeanBuilder, set JAVA_HOME to the PITBUILD binaries.
Invoke the BeanBuilder. Add some components to the Frame and click on save. Give a file name and clik The following exceptions is thrown at the prompt.

java version "swing-jcg-win-01-2004-06-16-int.tiger"
Java(TM) 2 Runtime Environment, Standard Edition (build swing-jcg-win-01-2004-06
-16-int.tiger)
Java HotSpot(TM) Client VM (build 1.5.0-beta3-b55, mixed mode)

Bean Builder Startup Time (ms): 11006
java.lang.ClassNotFoundException: javax.swing.SpringLayout$HeightSpring
        at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:290)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:279)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:236)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:303)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at beantest.util.SpringLayoutPersistenceDelegate.configure(Unknown Sourc
e)
        at beantest.BeanBuilder.handleSave(Unknown Source)
        at beantest.BeanBuilder.handleSaveAs(Unknown Source)
        at beantest.BeanBuilder.actionPerformed(Unknown Source)
        at com.sun.java.swing.action.ActionManager.doAction(Unknown Source)
        at com.sun.java.swing.action.ActionManager$1.run(Unknown Source)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchTh
read.java:234)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThre
ad.java:163)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)

        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)

        at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)