Bug 178519 Problems in multi-rows header
Please see the attachments.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/layout/pdf/PDFTableGroupLM.java
return;
		}
		if ( header.getChildren( ).isEmpty( ) )
		{
			return;
		}
		if ( child != null )
		{
			IContent content = child.getContent( );
			if ( content instanceof ITableBandContent )
			{
				if ( ( (ITableBandContent) content ).getBandType( ) == IBandContent.BAND_GROUP_HEADER )
				{
					return;
				}
			}
		}
		PDFReportLayoutEngine engine = context.getLayoutEngine( );
		PDFLayoutEngineContext con = new PDFLayoutEngineContext( engine );
		con.setFactory( new PDFLayoutManagerFactory( con ) );
		con.setFormat( context.getFormat( ) );
		con.setReport( context.getReport( ) );
		con.setMaxHeight( context.getMaxHeight( ) );
		con.setMaxWidth( context.getMaxWidth( ) );
		con.setAllowPageBreak( false );
		IReportItemExecutor headerExecutor = new DOMReportItemExecutor( header );
		headerExecutor.execute( );
		PDFTableRegionLM regionLM = new PDFTableRegionLM( con, tableLM
				.getContent( ), tableLM.getLayoutInfo( ) );
		regionLM.initialize( header, null );