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/api/script/instance/IReportElementInstance.java
void setWidth( String width );
	/**
	 * Get the height of the element
	 * 
	 */
	String getHeight( );
	/**
	 * Set the height of the element
	 * 
	 */
	void setHeight( String height );
	/** Get the value of a named expression
	 * 
	 */
	Object getNamedExpressionValue( String name );
	/** Get the value of a user property
	 * 
	 */
	Object getUserPropertyValue( String name );
	/** Set the value of a user property
	 * 
	 */
	void setUserPropertyValue( String name, Object value )
			throws ScriptException;
	/** Get the parent (container) of this element
	 * 
	 */
	IReportElementInstance getParent( );
}