(mx.messaging.messages::RemotingMessage)#0

 body = (Array)#1

 clientId = (null)

 destination = ""

 headers = (Object)#2

 messageId = "9D7C932F-AFFA-26C1-F624-C1EA7B88DB1B"

 operation = "getAllClasses"

 source = (null)

 timestamp = 0

timeToLive = 0

从异常信息中可以发现destination值为空字符串，根本原因是配置文件remoting-config.xml中没有定义destination对应的调用目标。

比如

var classesDao : RemoteObject = new RemoteObject("ClassesDao");