Bug 135790 ClassCastException in RowData.
ClassCastException is thrown in RowData line 81(IBaseExpression expr = ( IBaseExpression ) valueExpressions.get( index - 1 );).
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/executor/TableItemExecutor.java
cellContent.setColSpan( cell.getColSpan( ) );
				cellContent.setRowSpan( cell.getRowSpan( ) );
				processStyle( cell, cellContent );
				processVisibility( cell, cellContent );
				processBookmark( cell, cellContent );
				processAction( cell, cellContent );
				if ( context.isInFactory( ) )
				{
					CellScriptExecutor.handleOnCreate(
							( CellContent ) cellContent, rowData, context,
							false );
				}
				startTOCEntry( cellContent );
				if ( emitter != null )
				{
					emitter.startCell( cellContent );
				}
				for ( int m = 0; m < cell.getContentCount( ); m++ )
				{
					ReportItemDesign item = cell.getContent( m );
					if ( item != null )
					{
						if ( layoutEmitter != null )
						{
							item.accept( this.visitor, layoutEmitter
									.getCellEmitter( ) );
						} else
						{
							item.accept( this.visitor, emitter );
						}