An exception occurs when trying to render a dataTable when all of it's header rows (rows within a columnGroup of type header) are rendered=false.

java.lang.RuntimeException: failed to append text[
] into #document
at org.icefaces.impl.context.DOMResponseWriter.appendToCursor(DOMResponseWriter.java:435)
at org.icefaces.impl.context.DOMResponseWriter.appendToCursor(DOMResponseWriter.java:411)
at org.icefaces.impl.context.DOMResponseWriter.writeText(DOMResponseWriter.java:348)
at com.sun.faces.facelets.compiler.LiteralTextInstruction.write(LiteralTextInstruction.java:76)
at com.sun.faces.facelets.compiler.UIInstructions.encodeBegin(UIInstructions.java:82)
at com.sun.faces.facelets.compiler.UILeaf.encodeAll(UILeaf.java:207)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1822)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:447)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125)
at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:286)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1852)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
Caused by: org.w3c.dom.DOMException: HIERARCHY_REQUEST_ERR: An attempt was made to insert a node where it is not permitted.
at com.sun.org.apache.xerces.internal.dom.ParentNode.internalInsertBefore(ParentNode.java:360)
at com.sun.org.apache.xerces.internal.dom.ParentNode.insertBefore(ParentNode.java:288)
at com.sun.org.apache.xerces.internal.dom.CoreDocumentImpl.insertBefore(CoreDocumentImpl.java:404)
at com.sun.org.apache.xerces.internal.dom.NodeImpl.appendChild(NodeImpl.java:238)
at org.icefaces.impl.context.DOMResponseWriter.appendToCursor(DOMResponseWriter.java:430)
... 29 more

To reproduce:
1) Deploy test app located at: http://server.ice:8888/svn/repo/qa/trunk/Regression-Icefaces2/Sparkle/Nightly/dataTable
2) Navigate to 'MultiRow Header Test'
3) De-select the checkboxes that have 'Row' beside them (exception occurs).