[#4064] - Error when adding column header in table

Dear all, I use table with column header and it can be previewed using internal preview in ireport designer.

However, when I put the jasper file in server and run it, the following error occurs.

Even I try to use the latest version jasperreport-6.0.0.jar, same error occurs.

I also try the sample jrxml provided by project.zip, same error occurs.

If I remove column header, no error occurs.

I have no idea what I can do. Thanks.

Caused by: java.lang.NullPointerException at net.sf.jasperreports.components.table.fill.TableReport$ColumnHeaderCreator.addHeaderToolbarElement(TableReport.java:579) at net.sf.jasperreports.components.table.fill.TableReport$ColumnHeaderCreator.createColumnCell(TableReport.java:437) at net.sf.jasperreports.components.table.fill.TableReport$ReportBandCreator.visitColumn(TableReport.java:255) at net.sf.jasperreports.components.table.fill.TableReport$ReportBandCreator.visitColumn(TableReport.java:231) at net.sf.jasperreports.components.table.StandardColumn.visitColumn(StandardColumn.java:73) at net.sf.jasperreports.components.table.fill.TableReport$ReportBandCreator.visit(TableReport.java:310) at net.sf.jasperreports.components.table.fill.TableReport.createColumnHeader(TableReport.java:650) at net.sf.jasperreports.components.table.fill.TableReport.<init>(TableReport.java:157) at net.sf.jasperreports.components.table.fill.FillTable.createFillTableSubreport(FillTable.java:284) at net.sf.jasperreports.components.table.fill.FillTable.createFillSubreport(FillTable.java:260) at net.sf.jasperreports.components.table.fill.FillTable.evaluate(FillTable.java:105) at net.sf.jasperreports.engine.fill.JRFillComponentElement.evaluate(JRFillComponentElement.java:88) at net.sf.jasperreports.engine.fill.JRFillElementContainer.evaluate(JRFillElementContainer.java:257) at net.sf.jasperreports.engine.fill.JRFillBand.evaluate(JRFillBand.java:472) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillTitle(JRVerticalFiller.java:337) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReportStart(JRVerticalFiller.java:273) at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:144) at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:891) at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:823) at net.sf.jasperreports.engine.fill.JRFiller.fill(JRFiller.java:88) at net.sf.jasperreports.engine.JasperFillManager.fill(JasperFillManager.java:653) at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:969) ... 21 more