MQTT Binding for Azure IOT Hub

I’m trying to connect to Azure IoT Hub. I’ve tried with OH2 and today with OH2.1 but I keep seeing this in the log:

Starting MQTT broker connection 'mqttbroker’
2017-06-28 19:46:06.738 [ERROR] [penhab.io.transport.mqtt.MqttService] - Error starting broker connection
Connection lost (32109)

I can connect to Azure IoT hub just fine using mosquitto_sub like this on the same RPi as OpenHAB is running on:

mosquitto_sub -h OpenHab.azure-devices.net -p 8883 -t “devices/[DeviceID]/messages/devicebound/#” -i [DeviceID] -u “[HostName]/[DeviceID]” -P “SharedAccessSignature sr=[HostName]&sig=<…>se=<…>&skn=iothubowner” --capath /etc/ssl/certs/ --tls-version tlsv1 -d -V mqttv311 -q 1

I’ve configured mqtt.cfg like this:

mqtt:mqttbroker5.url=ssl://[HostName]:8883
mqtt:mqttbroker5.clientId=[DeviceID]
mqtt:mqttbroker5.user=[HostName]/[DeviceID]
mqtt:mqttbroker5.pwd=SharedAccessSignature=SharedAccessSignature sr=[HostName]&sig=[…key…]se=[……]&skn=iothubowner

Any hints? Has anyone managed to bind to Azure IoT Hub from OH2.x using MQTT binding?