Try to import Swing 1.0 (swingall.jar) into JWS 2.0 palette and got this:
(Same thing happens in jun97 beanbox: See evaluation)

java.lang.ExceptionInInitializerError
at java.lang.Throwable.<init>(Compiled Code)
at java.lang.Error.<init>(Compiled Code)
at java.lang.LinkageError.<init>(Compiled Code)
at java.lang.ExceptionInInitializerError.<init>(Compiled Code)
at java.lang.ClassLoader.resolveClass(Compiled Code)
at sunsoft.jws.visual.designer.loader.VJClassLoader.applyDefinition(Compiled Code)
at sunsoft.jws.visual.designer.loader.VJClassLoader.applyDefinitions(Compiled Code)
at sunsoft.jws.visual.designer.loader.VJJarLoader.defineIt(Compiled Code)
at sunsoft.jws.visual.designer.loader.VJJarLoader.<init>(Compiled Code)
at sunsoft.jws.visual.designer.loader.VJJarLoader.getVJJarLoader(Compiled Code)
at sunsoft.jws.visual.designer.loader.VJJarLoader.getVJJarLoader(Compiled Code)
at sunsoft.jws.visual.designer.importer.ImportBeans.loadJar(Compiled Code)
at sunsoft.jws.visual.designer.importer.ImportBeans.trigger(Compiled Code)
at sunw.kfc.beans.filebrowser.FileBrowserPanel.notifyListenersAux(Compiled Code)
at sunw.kfc.beans.filebrowser.FileBrowserPanel.notifyListeners(Compiled Code)
at sunw.kfc.beans.filebrowser.FileBrowserPanel.actionPerformed(Compiled Code)
at java.awt.Button.processActionEvent(Compiled Code)
at java.awt.Button.processEvent(Compiled Code)
at java.awt.Component.dispatchEventImpl(Compiled Code)
at java.awt.Component.dispatchEvent(Compiled Code)
at java.awt.EventDispatchThread.run(Compiled Code)
Visual Palette Editor Log : Error: This jar file swingall.jar is not loadable or introspectable.

Swing 1.0 has fixed the problem of Swing 0.7 not being able to be loaded in any IDE.