diff --git a/webssh/handler.py b/webssh/handler.py
index 43db8bd..5aaeef8 100644
--- a/webssh/handler.py
+++ b/webssh/handler.py
@@ -380,7 +380,7 @@ class IndexHandler(MixinHandler, tornado.web.RequestHandler):
     def get_source_address(self):
         value = self.get_value('source_address')
         if not is_valid_ip_address(value):
-            raise InvalidValueError('Invalid ip address: {}'.format(value))
+            raise InvalidValueError('Invalid source ip address: {}'.format(value))
         return value
 
     def lookup_hostname(self, hostname, port):
@@ -401,7 +401,7 @@ class IndexHandler(MixinHandler, tornado.web.RequestHandler):
         privatekey, filename = self.get_privatekey()
         passphrase = self.get_argument('passphrase', u'')
         totp = self.get_argument('totp', u'')
-        source_address = self.get_argument('source_address', u'')
+        source_address = self.get_source_address()
 
         if isinstance(self.policy, paramiko.RejectPolicy):
             self.lookup_hostname(hostname, port)
@@ -411,8 +411,19 @@ class IndexHandler(MixinHandler, tornado.web.RequestHandler):
         else:
             pkey = None
 
+        if source_address:
+            logging.info("Binding socket for source ip {}".format(source_address))
+            sock = socket.socket()
+            sock.settimeout(options.timeout)  # Set a timeout on blocking socket operations
+            try:
+                sock.bind((source_address, 0))
+            except OSError:
+                raise InvalidValueError('Unable to bind source address {} socket'.format(source_address))
+        else:
+            sock = None
+
         self.ssh_client.totp = totp
-        args = (hostname, port, username, password, pkey, source_address)
+        args = (hostname, port, username, password, pkey, sock)
         logging.debug(args)
 
         return args
@@ -458,17 +469,16 @@ class IndexHandler(MixinHandler, tornado.web.RequestHandler):
         dst_addr = args[:2]
         logging.info('Connecting to {}:{}'.format(*dst_addr))
 
-        # WIP ZM
-        sock = socket.socket()
-        sock.settimeout(5)  # otherwise it will hang if host is unreachable
-        sock.bind((args[5], 0))
-        print(args)
-        sock.connect((args[0], args[1]))
-
-
+        sock = args[5]
+        if sock:
+            logging.info('Connecting source address socket')
+            try:
+                sock.connect(dst_addr)
+            except socket.error:
+                raise ValueError('Unable to connect source address socket to {}:{}'.format(*dst_addr))
 
         try:
-            ssh.connect(*args, timeout=options.timeout, sock=sock)
+            ssh.connect(*args, timeout=options.timeout)
         except socket.error:
             raise ValueError('Unable to connect to {}:{}'.format(*dst_addr))
         except paramiko.BadAuthenticationType:
diff --git a/webssh/templates/index.html b/webssh/templates/index.html
index 3268c38..4b27e32 100644
--- a/webssh/templates/index.html
+++ b/webssh/templates/index.html
@@ -77,6 +77,8 @@
             <input class="form-control" type="password" id="totp" name="totp" value="">
           </div>
           <div class="col">
+            <label for="source_address">Source Address (optional)</label>
+            <input class="form-control" type="text" id="source_address" name="source_address" value="">
           </div>
         </div>
         <input type="hidden" id="term" name="term" value="xterm-256color">