Bug 182680 Use feature of new Aggregation framework of Data Engine.
DataEngine will implement new aggregation framework in 2.2.0RC0. After the implementation is finished Engine should go ahead to use new column bindings in definition of map/highlight.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
* @param value
	 *            value string
	 * @param valueType
	 *            value type
	 * @return object with the specified value
	 */
	private Object getStringValue( String value, String valueType )
	{
		try
		{
			if ( DesignChoiceConstants.PARAM_TYPE_BOOLEAN.equals( valueType ) )
				return DataTypeUtil.toBoolean( value );
			if ( DesignChoiceConstants.PARAM_TYPE_DATETIME.equals( valueType ) )
				return DataTypeUtil.toDate( value );
			if ( DesignChoiceConstants.PARAM_TYPE_DATE.equals( valueType ) )
				return DataTypeUtil.toSqlDate( value );
			if ( DesignChoiceConstants.PARAM_TYPE_TIME.equals( valueType ) )
				return DataTypeUtil.toSqlTime( value );
			if ( DesignChoiceConstants.PARAM_TYPE_DECIMAL.equals( valueType ) )
				return DataTypeUtil.toBigDecimal( value );
			if ( DesignChoiceConstants.PARAM_TYPE_FLOAT.equals( valueType ) )
				return DataTypeUtil.toDouble( value );
			if ( DesignChoiceConstants.PARAM_TYPE_INTEGER.equals( valueType ) )
				return DataTypeUtil.toInteger( value );
		}
		catch ( BirtException e )
		{
			log.log( Level.SEVERE, e.getLocalizedMessage( ), e );
		}
		return value;