Eclipse 4.2 customize perspective error

Hi

Clicking on Window -> Customize perspective ...

The window doesnt show up and the following error gets logged in "Error log":

java.lang.ClassCastException: org.eclipse.e4.ui.model.application.ui.menu.impl.OpaqueToolItemImpl cannot be cast to org.eclipse.e4.ui.model.application.ui.basic.MTrimElement
at org.eclipse.ui.internal.CoolBarToTrimManager.find(CoolBarToTrimManager.java:266)
at org.eclipse.ui.internal.WorkbenchWindowConfigurer$WindowActionBarConfigurer.containsCoolItem(WorkbenchWindowConfigurer.java:180)
at org.eclipse.ui.internal.WorkbenchWindowConfigurer.containsCoolItem(WorkbenchWindowConfigurer.java:501)
at org.eclipse.ui.internal.WorkbenchWindow.isWorkbenchCoolItemId(WorkbenchWindow.java:1549)
at org.eclipse.ui.internal.PluginActionSetBuilder$ActionSetContribution.isValidCoolItemId(PluginActionSetBuilder.java:488)
at org.eclipse.ui.internal.PluginActionSetBuilder$ActionSetContribution.contributeCoolbarAction(PluginActionSetBuilder.java:448)
at org.eclipse.ui.internal.PluginActionSetBuilder$ActionSetContribution.contribute(PluginActionSetBuilder.java:376)
at org.eclipse.ui.internal.PluginActionSetBuilder.buildMenuAndToolBarStructure(PluginActionSetBuilder.java:99)
at org.eclipse.ui.internal.dialogs.CustomizePerspectiveDialog.buildMenusAndToolbarsFor(CustomizePerspectiveDialog.java:2718)
at org.eclipse.ui.internal.dialogs.CustomizePerspectiveDialog.loadMenuAndToolbarStructure(CustomizePerspectiveDialog.java:2670)
at org.eclipse.ui.internal.dialogs.CustomizePerspectiveDialog.<init>(CustomizePerspectiveDialog.java:1483)
at org.eclipse.ui.internal.WorkbenchWindow.createCustomizePerspectiveDialog(WorkbenchWindow.java:2569)

.............. This error only occurs with wireframesketcher installed.

Is this some kind of incompatibility with eclipse juno 4.2?

From the error it looks like this is a bug with Eclipse itself. I could reproduce it. I'll file a bug for Eclipse developers to take a look. I'll let you know when I have more information.

I filed an Eclipse bug here: https://bugs.eclipse.org/bugs/show_bug.cgi?id=391957

Ok! Thank you.