Exception when sending xxforms-upload-start

gistfile1.txt

<xxforms:event-request xmlns:xxforms="http://orbeon.org/oxf/xml/xforms">
    <xxforms:uuid>46AFE50E-6980-6EE8-C78A-D12CF0AD57C9</xxforms:uuid>
    <xxforms:sequence>2</xxforms:sequence>
    <xxforms:action>
        <xxforms:event name="xxforms-upload-start" source-control-id="xf-20·1"/>
    </xxforms:action>
</xxforms:event-request>

java.lang.NullPointerException
	at org.orbeon.oxf.xforms.XFormsContainingDocument.startUpload(XFormsContainingDocument.java:1586)
	at org.orbeon.oxf.xforms.control.controls.XFormsUploadControl.performDefaultAction(XFormsUploadControl.java:82)
	at org.orbeon.oxf.xforms.xbl.XBLContainer.dispatchEvent(XBLContainer.java:1029)
	at org.orbeon.oxf.xforms.XFormsContainingDocument.dispatchEvent(XFormsContainingDocument.java:1090)
	at org.orbeon.oxf.xforms.XFormsContainingDocument.dispatchEventCheckTarget(XFormsContainingDocument.java:1005)
	at org.orbeon.oxf.xforms.XFormsContainingDocument.handleExternalEvent(XFormsContainingDocument.java:987)
	at org.orbeon.oxf.xforms.processor.XFormsServer.createAndDispatchEvents(XFormsServer.java:499)
	at org.orbeon.oxf.xforms.processor.XFormsServer.doIt(XFormsServer.java:249)
	at org.orbeon.oxf.xforms.processor.XFormsServer.access$000(XFormsServer.java:45)
	at org.orbeon.oxf.xforms.processor.XFormsServer$1.readImpl(XFormsServer.java:77)
	at org.orbeon.oxf.processor.impl.ProcessorOutputImpl$TopLevelOutputFilter.read(ProcessorOutputImpl.java:263)
	at org.orbeon.oxf.processor.impl.ProcessorOutputImpl.read(ProcessorOutputImpl.java:406)
	at org.orbeon.oxf.processor.ProcessorImpl.readInputAsSAX(ProcessorImpl.java:257)
	at org.orbeon.oxf.processor.pipeline.TeeProcessor.access$200(TeeProcessor.java:32)
	at org.orbeon.oxf.processor.pipeline.TeeProcessor$TeeProcessorOutputImpl.readImpl(TeeProcessor.java:89)
	at org.orbeon.oxf.processor.impl.ProcessorOutputImpl$TopLevelOutputFilter.read(ProcessorOutputImpl.java:263)
	at org.orbeon.oxf.processor.impl.ProcessorOutputImpl.read(ProcessorOutputImpl.java:406)
	at org.orbeon.oxf.processor.ProcessorImpl.readInputAsSAX(ProcessorImpl.java:257)
	at org.orbeon.oxf.processor.ProcessorImpl.readInputAsTinyTree(ProcessorImpl.java:283)
	at org.orbeon.oxf.processor.ProcessorImpl$3.read(ProcessorImpl.java:316)
	at org.orbeon.oxf.processor.ProcessorImpl.readCacheInputAsObject(ProcessorImpl.java:391)
	at org.orbeon.oxf.processor.ProcessorImpl.readCacheInputAsObject(ProcessorImpl.java:331)
	at org.orbeon.oxf.processor.ProcessorImpl.readCacheInputAsTinyTree(ProcessorImpl.java:314)
	at org.orbeon.oxf.processor.pipeline.choose.ConcreteChooseProcessor.start(ConcreteChooseProcessor.java:186)
	at org.orbeon.oxf.processor.pipeline.PipelineProcessor$5.run(PipelineProcessor.java:661)
	at org.orbeon.oxf.processor.pipeline.PipelineProcessor.executeChildren(PipelineProcessor.java:726)
	at org.orbeon.oxf.processor.pipeline.PipelineProcessor.start(PipelineProcessor.java:658)
	at org.orbeon.oxf.processor.pipeline.choose.ConcreteChooseProcessor.start(ConcreteChooseProcessor.java:248)
	at org.orbeon.oxf.processor.pipeline.PipelineProcessor$5.run(PipelineProcessor.java:661)
	at org.orbeon.oxf.processor.pipeline.PipelineProcessor.executeChildren(PipelineProcessor.java:726)
	at org.orbeon.oxf.processor.pipeline.PipelineProcessor.start(PipelineProcessor.java:658)
	at org.orbeon.oxf.pipeline.InitUtils.runProcessor(InitUtils.java:83)
	at org.orbeon.oxf.webapp.ProcessorService.service(ProcessorService.java:97)
	at org.orbeon.oxf.servlet.OrbeonServletDelegate.service(OrbeonServletDelegate.java:133)