SEVERE: null when eval INDIRECT("Dummy_for_Comparison1!"&ADDRESS(ROW(),COLUMN()))
java.lang.NullPointerException
	at org.zkoss.zss.model.impl.sys.formula.DependencyTrackerImpl.clearIndirectRefPrecedent(DependencyTrackerImpl.java:76)
	at org.zkoss.poi.ss.formula.OperationEvaluationContext.clearIndirectRefPrecedent(OperationEvaluationContext.java:431)
	at org.zkoss.poi.ss.formula.OperationEvaluationContext.getDynamicReference(OperationEvaluationContext.java:184)
	at org.zkoss.poi.ss.formula.functions.Indirect.evaluateIndirect(Indirect.java:126)
	at org.zkoss.poi.ss.formula.functions.Indirect.evaluate(Indirect.java:76)
	at org.zkoss.poi.ss.formula.OperationEvaluatorFactory.evaluate(OperationEvaluatorFactory.java:137)
	at org.zkoss.poi.ss.formula.WorkbookEvaluator.evaluateFormula(WorkbookEvaluator.java:594)
	at org.zkoss.poi.ss.formula.WorkbookEvaluator.evaluateAny(WorkbookEvaluator.java:991)
	at org.zkoss.poi.ss.formula.WorkbookEvaluator.evaluate(WorkbookEvaluator.java:912)
	at org.zkoss.zss.model.impl.sys.formula.FormulaEngineImpl.evaluateFormulaExpression(FormulaEngineImpl.java:1362)
	at org.zkoss.zss.model.impl.sys.formula.FormulaEngineImpl.evaluateFormula(FormulaEngineImpl.java:520)
	at org.zkoss.zss.model.impl.sys.formula.FormulaEngineImpl.evaluate(FormulaEngineImpl.java:408)
	at org.zkoss.zss.model.impl.RuleInfo.evalFormula(RuleInfo.java:87)
	at org.zkoss.zss.range.impl.BaseMatch2.match(BaseMatch2.java:58)
	at org.zkoss.zss.range.impl.BaseMatch2.match(BaseMatch2.java:31)
	at org.zkoss.zss.range.impl.CellMatch2$MatchOne.match0(CellMatch2.java:100)
	at org.zkoss.zss.range.impl.CellMatch2$MatchOne.match(CellMatch2.java:94)
	at org.zkoss.zss.range.impl.CellMatch2.match(CellMatch2.java:51)
	at org.zkoss.zss.range.impl.CellMatch2.match(CellMatch2.java:1)
	at org.zkoss.zss.model.impl.ConditionalFormattingRuleImpl.match(ConditionalFormattingRuleImpl.java:315)
	at org.zkoss.zss.model.impl.SheetImpl.getConditionalFormattingStyle(SheetImpl.java:2330)
	at org.zkoss.zss.ui.impl.CellFormatHelper.processBottomBorder(CellFormatHelper.java:192)
	at org.zkoss.zss.ui.impl.CellFormatHelper.getHtmlStyle(CellFormatHelper.java:145)
	at org.zkoss.zss.ui.Spreadsheet$ExtraCtrl.getCellAttr(Spreadsheet.java:3712)
	at org.zkoss.zss.ui.Spreadsheet$ExtraCtrl.getRangeAttrs(Spreadsheet.java:3551)
	at org.zkoss.zss.ui.au.in.FetchActiveRangeCommand.process(FetchActiveRangeCommand.java:62)
	at org.zkoss.zss.ui.Spreadsheet.service(Spreadsheet.java:6156)
	at org.zkoss.zk.ui.impl.DesktopImpl.service(DesktopImpl.java:758)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execUpdate(UiEngineImpl.java:1310)
	at org.zkoss.zk.au.http.DHtmlUpdateServlet.process(DHtmlUpdateServlet.java:606)
	at org.zkoss.zk.au.http.DHtmlUpdateServlet.doGet(DHtmlUpdateServlet.java:482)
	at org.zkoss.zk.au.http.DHtmlUpdateServlet.doPost(DHtmlUpdateServlet.java:490)