Rotating on iPhone with Safari?

Hi,

I was running appium 1.2.1 with a iPhone 7.1 for a web test on safari, and was trying to rotate the phone during the session. However I saw this error happened, any idea?

2014-10-27 17:02:14:285 - info: --> POST /wd/hub/session/dafbf15a-9304-4b77-b8fe-233dbe50cc33/orientation {“orientation”:“PORTRAIT”}
2014-10-27 17:02:14:287 - debug: Pushing command to appium work queue: “au.setScreenOrientation(‘PORTRAIT’)”
2014-10-27 17:02:14:288 - debug: Sending command to instruments: au.setScreenOrientation(‘PORTRAIT’)
2014-10-27 17:02:14:289 - debug: Sending command to instruments: au.setScreenOrientation(‘PORTRAIT’)
2014-10-27 17:02:15:079 - debug: Socket data received (49 bytes)
2014-10-27 17:02:15:080 - debug: Socket data being routed.
2014-10-27 17:02:15:080 - debug: Got result from instruments: {“status”:17,“value”:“Can’t find variable: au”}
2014-10-27 17:02:15:081 - debug: Responding to client with error: {“status”:17,“value”:{“message”:“An error occurred while executing user supplied JavaScript.”,“origValue”:“Can’t find variable: au”},“sessionId”:“dafbf15a-9304-4b77-b8fe-233dbe50cc33”}
2014-10-27 17:02:15:082 - info: <-- POST /wd/hub/session/dafbf15a-9304-4b77-b8fe-233dbe50cc33/orientation 500 797.439 ms - 184