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
protected void createRoot( )
	{
		if ( root == null )
		{
			root = (ContainerArea) AreaFactory.createBlockContainer( content );
		}
	}
	protected void initialize( )
	{
		if ( root == null && keepWithCache.isEmpty( ) && !isFirst )
		{
			repeatCount = 0;
			needRepeat = true;
		}
		super.initialize( );
	}
	private void repeat( )
	{
		if ( isFirst || tableLM.isFirst )
		{
			isFirst = false;
			return;
		}
		if ( !needRepeat || !isCurrentDetailBand( ) )
		{
			return;
		}
		ITableBandContent header = (ITableBandContent) groupContent.getHeader( );
		if ( !isRepeatHeader( ) || header == null )
		{