环信SDK为何在from":null时SDK奔溃求大神指教

正常：日志
{"from":"d1369df4bae79852124103d1404c2805","to":"1b36ea1c9b7a1c3ad668b8bb5df7963f","bodies":[{"msg":"{\"data\":{\"content\":\"咯\",\"contentType\":1,\"createTime\":1449486972885,\"questionUUID\":\"B661D834B5DF24C2DF3F8A81EC8B908CBC2EAE00A702F9A3042A98288BBC1DED\",\"speakerName\":\"F_601990\",\"speakerPic\":\",undefinedquot;extundefinedquot;:{}}]http://192.168.0.33/images/default/icon_nongmin.png\",\"speakerType\":1,\"speakerUUID\":\"D6D58FA1C246ED5775D7448D47FC058BBC2EAE00A702F9A3042A98288BBC1DED\",\"talkId\":3645},\"msgType\":1}","type":"txt"}],"ext":{}}​ 
错误：日志
{"from":null,"to":"1b36ea1c9b7a1c3ad668b8bb5df7963f","bodies":[{"msg":"{\"data\":{\"createTime\":1449486610475,\"expired\":120,\"question\":{\"affirmativeNum\":0,\"answer\":1984,\"answerCount\":0,\"answerNum\":0,\"answerScore\":0,\"answerUUID\":\"D1F2E9F65784FB241F22D48D3B40309C\",\"askAnswers\":[],\"asker\":0,\"askerHeadImg\":\"http://192.168.0.33/images/default/icon_nongmin.png\",\"askerName\":\"F_601990\",\"askerUUID\":\"D6D58FA1C246ED5775D7448D47FC058BBC2EAE00A702F9A3042A98288BBC1DED\",\"createTime\":1449486610475,\"dispatchType\":2,\"favorite\":false,\"id\":0,\"isAutoComment\":0,\"location\":\"北京市.海淀区\",\"negativeNum\":0,\"questionUUID\":\"CE3BE49A86A458A872F85C565434720FBC2EAE00A702F9A3042A98288BBC1DED\",\"sayHelpful\":0,\"specie\":\"花菜\",\"specieId\":0,\"status\":0,\"step\":1,\"title\":\"来咯\",\"viewTimes\":0},\"questionUUID\":\"CE3BE49A86A458A872F85C565434720FBC2EAE00A702F9A3042A98288BBC1DED\"},\"msgType\":5}","type":"txt"}],"ext":{}}
正常："from":"d1369df4bae79852124103d1404c2805"
奔溃："from":null,"to":
求大神求教