Extjs4.0.7 url is not defined BUG

ExtJS4.0.7版本中如果使用Tree时按如下方式调用在FF下会抛出

url is not defined 错误

这是4.0.7版本的一个BUG

 

var tree = Ext.getCmp("core_leftTree");
    	var treeStore = tree.getStore();
    	
    	treeStore.setProxy({ type: 'ajax',method:'post',url: url});
    	treeStore.load();

 官方在4.1版本已经做了修复

http://www.sencha.com/forum/showthread.php?154059-4.0.7-TreePanel-Error-when-reloading-the-treeStore