diff --git a/sensor/asterisk_ami.py b/sensor/asterisk_ami.py
index fe986e1..eb6ed8c 100644
--- a/sensor/asterisk_ami.py
+++ b/sensor/asterisk_ami.py
@@ -1,18 +1,28 @@
+"""Asterisk Sensors"""
+import logging
+
 from homeassistant.const import STATE_UNKNOWN
 from homeassistant.helpers.entity import Entity
 
 DATA_ASTERISK = 'asterisk'
 DATA_MONITOR = 'asterisk-monitor'
+DATA_MAILBOX = 'asterisk-mailbox'
 
+_LOGGER = logging.getLogger(__name__)
 
 def setup_platform(hass, config, add_devices, discovery_info=None):
+    """Sensor setup
+       Loads configuration and creates devices for extensions and mailboxes
+    """
     add_devices([AsteriskSensor(hass)])
     for extension in hass.data[DATA_MONITOR]:
         add_devices([AsteriskExtension(hass, extension)])
+    for mailbox in hass.data[DATA_MAILBOX]:
+        add_devices([AsteriskMailbox(hass, mailbox)])
 
 
 class AsteriskSensor(Entity):
-    """Representation of a Sensor."""
+    """Asterisk Server connection status sensor."""
 
     def __init__(self, hass):
         """Initialize the sensor."""
@@ -34,13 +44,20 @@ def should_poll(self):
         return True
 
     def update(self):
+        """Check the connection status and update the internal state"""
         if self._hass.data[DATA_ASTERISK].connected():
             self._state = 'connected'
         else:
             self._state = 'disconnected'
+            try:
+                manager.connect(host, port)
+                login_status = manager.login(username=username, secret=password).get_header("Response")
+            except asterisk.manager.ManagerException as exception:
+                _LOGGER.error("Error connecting to Asterisk: %s", exception.args[1])
 
 
 class AsteriskExtension(Entity):
+    """SIP extension connection status (registration) sensor."""
     def __init__(self, hass, extension):
         self._hass = hass
         self._extension = extension
@@ -59,14 +76,45 @@ def should_poll(self):
         return True
 
     def update(self):
+        """Check the registration status and update the state"""
         response = self._hass.data[DATA_ASTERISK].sipshowpeer(self._extension)
         if response.get_header("Response", "Error") == "Error":
             self._state = STATE_UNKNOWN
             return
-        else:
-            status_header = response.get_header("Status", "unknown")
-            if "OK" in status_header:
-                self._state = "OK"
-                return
-            else:
-                self._state = status_header
+
+        status_header = response.get_header("Status", "unknown")
+        # OK state includes the connection latency, which needs removing
+        if "OK" in status_header:
+            self._state = "OK"
+
+        self._state = status_header
+
+class AsteriskMailbox(Entity):
+    """Voicemail Mailbox Sensor."""
+    def __init__(self, hass, mailbox):
+        self._hass = hass
+        self._mailbox = mailbox
+        self._state = STATE_UNKNOWN
+
+    @property
+    def name(self):
+        return "Asterisk Mailbox " + self._mailbox
+
+    @property
+    def state(self):
+        return self._state
+
+    @property
+    def should_poll(self):
+        return True
+
+    def update(self):
+        """Check the mailbox status and update the state"""
+        cdict = {'Action': 'MailboxStatus'}
+        cdict['Peer'] = self._mailbox
+        response = self._hass.data[DATA_ASTERISK].send_action(cdict)
+        _LOGGER.info(response)
+        _LOGGER.info(response.headers)
+        if response.get_header('Response') == 'Error':
+            raise Exception(response.get_header('Message'))
+        self._state = response.get_header('Waiting', STATE_UNKNOWN)