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
regionLM.layout( );
		TableArea tableRegion = (TableArea) tableLM.getContent( ).getExtension(
				IContent.LAYOUT_EXTENSION );
		if ( tableRegion != null
				&& tableRegion.getHeight( ) < getCurrentMaxContentHeight( ) )
		{
			
			Iterator iter = tableRegion.getChildren( );
			RowArea row = null;
			int count = 0;
			while ( iter.hasNext( ) )
			{
				row = (RowArea) iter.next( );
				
				addArea( row, false, true );
				tableLM.addRow( row, true );
				count++;
			}
			repeatCount += count;
		}
		tableLM.getContent( ).setExtension( IContent.LAYOUT_EXTENSION, null );
		needRepeat = false;
	}
	protected void repeatHeader( )
	{
		repeat( );
		skipCachedRow( );
	}
	protected IReportItemExecutor createExecutor( )
	{