导入环信3.0的EaseChatFragment后，发送消息时报空指针

如题，报的错误如下
06-27 21:25:30.629  27796-27796/org.superyu.palmlife E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: org.superyu.palmlife, PID: 27796
    java.lang.NullPointerException
            at com.hyphenate.easeui.model.EasePreferenceManager.(EasePreferenceManager.java:16)
            at com.hyphenate.easeui.model.EasePreferenceManager.getInstance(EasePreferenceManager.java:23)
            at com.hyphenate.easeui.model.EaseAtMessageHelper.(EaseAtMessageHelper.java:28)
            at com.hyphenate.easeui.model.EaseAtMessageHelper.get(EaseAtMessageHelper.java:21)
            at com.hyphenate.easeui.ui.EaseChatFragment.sendTextMessage(EaseChatFragment.java:661)
            at com.hyphenate.easeui.ui.EaseChatFragment$1.onSendMessage(EaseChatFragment.java:152)
            at com.hyphenate.easeui.widget.EaseChatInputMenu$1.onSendBtnClicked(EaseChatInputMenu.java:184)
            at com.hyphenate.easeui.widget.EaseChatPrimaryMenu.onClick(EaseChatPrimaryMenu.java:161)
            at android.view.View.performClick(View.java:4448)
            at android.view.View$PerformClick.run(View.java:18461)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5072)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
            at dalvik.system.NativeStart.main(Native Method)