diff --git a/mopidy/backends/spotify/session_manager.py b/mopidy/backends/spotify/session_manager.py
index 3e8f1b67..dff29fad 100644
--- a/mopidy/backends/spotify/session_manager.py
+++ b/mopidy/backends/spotify/session_manager.py
@@ -33,10 +33,12 @@ class SpotifySessionManager(process.BaseThread, PyspotifySessionManager):
         self.cache_location = config['spotify']['cache_dir']
         self.settings_location = config['spotify']['cache_dir']
 
-        # Add proxy port only if available
-        full_proxy = config['proxy']['hostname']
-        if 'port' in config['proxy']:
-            full_proxy = full_proxy + ':' + str(config['proxy']['port'])
+        full_proxy = ''
+        if config['proxy']['hostname']:
+            full_proxy = config['proxy']['hostname']
+            # Add proxy port only if available
+            if config['proxy']['port']:
+                full_proxy = full_proxy + ':' + str(config['proxy']['port'])
 
         PyspotifySessionManager.__init__(
             self, config['spotify']['username'], config['spotify']['password'],
diff --git a/mopidy/config/__init__.py b/mopidy/config/__init__.py
index 7ccaa3f3..35a1d8e0 100644
--- a/mopidy/config/__init__.py
+++ b/mopidy/config/__init__.py
@@ -29,7 +29,7 @@ _proxy_schema = ConfigSchema('proxy')
 _proxy_schema['hostname'] = Hostname(optional=True)
 _proxy_schema['username'] = String(optional=True)
 _proxy_schema['password'] = Secret(optional=True)
-_proxy_schema['port'] = Port(optional=True)
+_proxy_schema['port'] = Port()
 
 # NOTE: if multiple outputs ever comes something like LogLevelConfigSchema
 #_outputs_schema = config.AudioOutputConfigSchema()
diff --git a/mopidy/config/default.conf b/mopidy/config/default.conf
index 204c789b..4a259c49 100644
--- a/mopidy/config/default.conf
+++ b/mopidy/config/default.conf
@@ -16,4 +16,4 @@ output = autoaudiosink
 hostname =
 username =
 password =
-port =
\ No newline at end of file
+port =
diff --git a/mopidy/config/types.py b/mopidy/config/types.py
index 3dff0908..8309a591 100644
--- a/mopidy/config/types.py
+++ b/mopidy/config/types.py
@@ -117,10 +117,7 @@ class Integer(ConfigValue):
         self._choices = choices
 
     def deserialize(self, value):
-        try:
-            value = int(value)
-        except:
-            value = 0
+        value = int(value)
         validators.validate_choice(value, self._choices)
         validators.validate_minimum(value, self._minimum)
         validators.validate_maximum(value, self._maximum)
@@ -225,11 +222,29 @@ class Port(Integer):
     allocate a port for us.
     """
     # TODO: consider probing if port is free or not?
-    def __init__(self, choices=None, optional=False):
-        self._required = not optional        
+    def __init__(self, choices=None):
         super(Port, self).__init__(
             minimum=0, maximum=2 ** 16 - 1, choices=choices)
 
+    def deserialize(self, value):
+        # in case of no value is given, just return nothing
+        if not len(value):
+            return value
+        # now we can try to convert
+        try:
+            value = int(value)
+        except ValueError:
+            try:
+                value = socket.getservbyname(value, 'tcp')
+            except socket.error:
+                raise ValueError('must be a valid port number')
+        else:
+            validators.validate_choice(value, self._choices)
+            validators.validate_minimum(value, self._minimum)
+            validators.validate_maximum(value, self._maximum)
+        return value
+
+
 
 class Path(ConfigValue):
     """File system path