We have a test which do clip in the node, when run it in the browser IE7, we got the NullPointerExceptions.
The test case is attached and the exception is attached and the NullpointException is as following:

group: onMouseReleased
107: group: onMouseReleased

Exception in thread "AWT-EventQueue-2" java.lang.NullPointerException
at com.sun.scenario.scenegraph.SGEmbeddedToolkit.processMouseEvent(SGEmbeddedToolkit.java:166)
at com.sun.embeddedswing.EmbeddedEventQueue.beforeDispatch(EmbeddedEventQueue.java:240)
at com.sun.embeddedswing.EmbeddedEventQueue.access$400(EmbeddedEventQueue.java:70)
at com.sun.embeddedswing.EmbeddedEventQueue$EventQueueDelegateFactory$2.call(EmbeddedEventQueue.java:589)
at com.sun.java.swing.SwingUtilities3$EventQueueDelegateFromMap.beforeDispatch(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)