Microsoft SQL datasource quoting issue

app_controller.php

<?php
class AppController extends Controller {		
	function beforeFilter() {
		$this->loadModel('ErpContract');	
		debug($this->ErpContract->find('first', array(
			'fields' => array('No_', 'Change Order No_')
		)));
	}
}

database.php

<?php
class DATABASE_CONFIG {
	var $erp = array(
		'driver' => 'mssql',
		'persistent' => false,
		'host' => '',
		'login' => '',
		'password' => '',
		'database' => 'ADP_NAVISION',
		'prefix' => 'My Live Company$'
	);
}

erp_contract.php

<?php
class ErpContract extends AppModel {
	var $useDbConfig = 'erp';
	var $useTable = 'Contract';
}

gistfile4.txt

SQL Error: Incorrect syntax near 'No_'. [CORE\cake\libs\model\datasources\dbo_source.php, line 681]

Query: SELECT  TOP 1 [ErpContract].[No_] AS [ErpContract__0], ErpContract.Change Order No_ AS [ErpContract__1] FROM My Live Company$Contract AS [ErpContract]   WHERE 1 = 1