ios - 发送 iMessage 使用 madrid，CKMadridEntity 一直返回 nil

Question

//我正在修改这个 SMS 代码以使用 madrid

CKSMSService *smsService = [CKSMSService sharedSMSService];
CKConversationList *conversationList = nil;
conversationList = [CKConversationList sharedConversationList];
CKSMSEntity *ckEntity = [smsService copyEntityForAddressString:@\"555-555-5555\"];
CKConversation *conversation = [conversationList conversationForRecipients:[NSArray arrayWithObject:ckEntity] create:TRUE service:smsService];
NSString *groupID = [conversation groupID];
CKSMSMessage *ckMsg = [smsService _newSMSMessageWithText:msg forConversation:conversation];
[smsService sendMessage:ckMsg];
[ckMsg release]; 

//but CKMadridEntity kept returning nil (psuedo code)

CKMadridService *madridService = [CKMadridService sharedMadridService];
CKConversationList *conversationList = nil;
conversationList = [CKConversationList sharedConversationList];
CKMadridEntity *ckEntity = [madridService copyEntityForAddressString:@\"555-555-5555\"]; //tried @\"whoever@gmail.com\" too


**I am using xcode5.1, private api for ios5.1.

我想使用私有 api 发送带有 imessage 的短信，粘贴了 chatkit.framework 代码中的私有 api。所以我该怎么做？请帮我！！**