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/PDFTableLM.java
Iterator iter = area.getChildren( );
			while ( iter.hasNext( ) )
			{
				ContainerArea container = (ContainerArea) iter.next( );
				skip( container );
			}
		}
	}
	public class TableLayoutInfo
	{
		public TableLayoutInfo( int[] colWidth )
		{
			this.colWidth = colWidth;
			this.columnNumber = colWidth.length;
			this.xPositions = new int[columnNumber];
			this.tableWidth = 0;
			for ( int i = 0; i < columnNumber; i++ )
			{
				xPositions[i] = tableWidth;
				tableWidth += colWidth[i];
			}
		}
		public int getTableWidth( )
		{
			return this.tableWidth;
		}
		public int getXPosition( int index )
		{
			return xPositions[index];
		}