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/parser/EngineIRVisitor.java
*/
	private TableBandDesign createTableBand( SlotHandle elements )
	{
		TableBandDesign band = new TableBandDesign( );
		for ( int i = 0; i < elements.getCount( ); i++ )
		{
			apply( elements.get( i ) );
			if ( currentElement != null )
			{
				band.addRow( (RowDesign) currentElement );
			}
		}
		return band;
	}
	/**
	 * Creates the property visibility
	 * 
	 * @param visibilityRulesIterator
	 *            the handle's rules iterator
	 * @return null only if the iterator is null or it contains no rules,
	 *         otherwise VisibilityDesign
	 */
	protected VisibilityDesign createVisibility(
			Iterator visibilityRulesIterator )
	{
		if ( visibilityRulesIterator != null )
		{
			VisibilityDesign visibility = new VisibilityDesign( );
			while ( visibilityRulesIterator.hasNext( ) )
			{