RS in fill-in-blanck editor

I don't how someone can produce this red screen, it's not possible but...

RedScreen on node8 9.0.3
2013-09-24 11:49:54,858 [ajp-apr-8008-exec-20] ERROR OLATRuntimeException - OLAT::ERROR ^% N8-E44 ^% org.olat.core.logging
Mozilla/5.0 (Windows NT 5.2) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1
*RedScreen*
<dispatchinfo>
<componentinfo>
<compname>fibitem</compname>
<compclass>org.olat.core.gui.components.velocity.VelocityContainer</compclass>
<extendedinfo>page:org/olat/ims/qti/editor/_content/tab_fibItem.html</extendedinfo>
<event>
<class>org.olat.core.gui.control.Event</class>
<command>sfib</command>
<tostring>com:sfib,org.olat.core.gui.control.Event@35d2cb</tostring>
</event>
</componentinfo>
<controllerinfo>
<controllername>org.olat.ims.qti.editor.FIBItemController</controllername>
<controllername>org.olat.ims.qti.editor.ItemNodeTabbedFormController</controllername>
<controllername>org.olat.ims.qti.editor.QTIEditorMainController</controllername>
<controllername>org.olat.core.commons.fullWebApp.BaseFullWebappController</controllername>
<controllername>org.olat.core.commons.chiefcontrollers.controller.simple.SimpleBaseController</controllername>
<controllername>org.olat.core.commons.chiefcontrollers.BaseChiefController</controllername>
</controllerinfo>
</dispatchinfo>
>>> stack of 1.cause::org.olat.core.logging.OLATRuntimeException: null
-> at org.olat.core.gui.exception.ExceptionWindowController.<init>(ExceptionWindowController.java:107)
at org.olat.core.gui.exception.MsgFactory.createMessageChiefController(MsgFactory.java:57)
at org.olat.core.gui.exception.MsgFactory.createMessageChiefController(MsgFactory.java:46)
at org.olat.core.gui.components.Window.dispatchRequest(Window.java:508)
at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:226)
at org.olat.core.gui.components.Component.dispatchRequest(Component.java:192)
at org.olat.dispatcher.AuthenticatedDispatcher.execute(AuthenticatedDispatcher.java:227)
at org.olat.core.dispatcher.DispatcherAction.execute(DispatcherAction.java:154)
at org.olat.core.servlets.OLATServlet.doPost(OLATServlet.java:155)
at org.olat.core.servlets.OLATServlet.doGet(OLATServlet.java:128)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
>>> stack of 2.cause::java.lang.NullPointerException: null
-> at org.olat.ims.qti.editor.FIBItemController.event(FIBItemController.java:173)
at org.olat.core.gui.control.DefaultController.dispatchEvent(DefaultController.java:195)
at org.olat.core.gui.components.Component$1.run(Component.java:238)
at org.olat.core.logging.activity.ThreadLocalUserActivityLoggerInstaller.runWithUserActivityLogger(ThreadLocalUserActivityLoggerInstaller.java:108)
at org.olat.core.gui.components.Component.fireEvent(Component.java:236)
at org.olat.core.gui.components.velocity.VelocityContainer.doDispatchRequest(VelocityContainer.java:112)
at org.olat.core.gui.components.Component.dispatchRequest(Component.java:192)
at org.olat.core.gui.components.Window.doDispatchToComponent(Window.java:1137)
at org.olat.core.gui.components.Window.dispatchRequest(Window.java:335)
at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:226)
at org.olat.core.gui.components.Component.dispatchRequest(Component.java:192)