Error produced when SafariLauncher loads

nfo: Launching instruments
info: [debug] Attempting to run app on real device with UDID e1df26e5d64c46fbf287180f33c9c116a10e86dc
info: [debug] Spawning instruments with command: /Applications/Xcode.app/Contents/Developer/usr/bin/instruments -t /Applications/Xcode.app/Contents/Applications/Instruments.app/Contents/PlugIns/AutomationInstrument.xrplugin/Contents/Resources/Automation.tracetemplate -D /tmp/appium-instruments/instrumentscli0.trace -w e1df26e5d64c46fbf287180f33c9c116a10e86dc com.bytearc.SafariLauncher -e UIASCRIPT “/Users/fdiaz/Library/Application Support/appium/bootstrap/bootstrap-e4831d36bd5a5f5a.js” -e UIARESULTSPATH /tmp/appium-instruments
info: [debug] And extra without-delay env: {}
info: [debug] And launch timeouts (in ms): {“global”:90000}
info: [debug] [INST STDERR] 2015-07-07 12:17:16.690 instruments[75109:11641168] WebKit Threading Violation - initial use of WebKit from a secondary thread.
info: [debug] [INST STDERR] 2015-07-07 12:17:20.966 instruments[75109:11641168] Automation Instrument ran into an exception while trying to run the script. UIAScriptAgentSignaledException
info: [debug] [INST] 2015-07-07 16:17:20 +0000 Fail: An error occurred while trying to run the script.
info: [debug] [INST] Instruments Trace Complete (Duration : 4.791124s; Output : /tmp/appium-instruments/instrumentscli0.trace)
info: [debug] [INSTSERVER] Instruments exited with code 0
info: [debug] Cleaning up after instruments exit
info: [debug] Not worrying about instruments exit since we’re using SafariLauncher
info: <-- POST /wd/hub/session - - ms - -
info: --> POST /wd/hub/session {“desiredCapabilities”:{“uid”:“e1df26e5d64c46fbf287180f33c9c116a10e86dc”,“platformName”:“iOS”,“platformVersion”:“8.3”,“browserName”:“Safari”,“deviceName”:“iPhone”}}
info: Client User-Agent string: undefined
error: Failed to start an Appium session, err was: Error: Requested a new session but one was in progress
info: [debug] Error: Requested a new session but one was in progress
at [object Object].Appium.start (/Users/fdiaz/DevTools/appium/lib/appium.js:139:15)
at exports.createSession (/Users/fdiaz/DevTools/appium/lib/server/controller.js:188:16)
at Layer.handle [as handle_request] (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/layer.js:82:5)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:110:13)
at Route.dispatch (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:91:3)
at Layer.handle [as handle_request] (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/layer.js:82:5)
at /Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:267:22
at Function.proto.process_params (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:321:12)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:261:10)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:100:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at /Users/fdiaz/DevTools/appium/lib/server/controller.js:39:7
at Layer.handle [as handle_request] (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/layer.js:82:5)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:110:13)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:104:14)
at Route.dispatch (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/route.js:91:3)
at Layer.handle [as handle_request] (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/layer.js:82:5)
at /Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:267:22
at Function.proto.process_params (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:321:12)
at next (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:261:10)
at methodOverride (/Users/fdiaz/DevTools/appium/node_modules/method-override/index.js:77:5)
at Layer.handle [as handle_request] (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/layer.js:82:5)
at trim_prefix (/Users/fdiaz/DevTools/appium/node_modules/express/lib/router/index.js:302:13)
info: [debug] Responding to client with error: {“status”:33,“value”:{“message”:“A new session could not be created. (Original error: Requested a new session but one was in progress)”,“origValue”:“Requested a new session but one was in progress”},“sessionId”:“fe0d8a61-10a2-4823-b837-89fb9c4c7f1d”}