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
* @version $Revision: 1.90 $ $Date: 2006/03/31 09:54:23 $
 */
class EngineIRVisitor extends DesignVisitor
{
	/**
	 * logger used to log the error.
	 */
	protected static Logger logger = Logger.getLogger( EngineIRVisitor.class
			.getName( ) );
	/**
	 * current report element created by visitor
	 */
	protected Object currentElement;
	/**
	 * default unit used by this report
	 */
	protected String defaultUnit;
	/**
	 * Factory IR created by this visitor
	 */
	protected Report report;
	/**
	 * report design handle
	 */
	protected ReportDesignHandle handle;
	/**
	 * the CSSEngine
	 */
	protected CSSEngine cssEngine;
	/**