diff --git a/letsencrypt/client/CONFIG.py b/letsencrypt/client/CONFIG.py
index 7d0b581fb..e65277221 100644
--- a/letsencrypt/client/CONFIG.py
+++ b/letsencrypt/client/CONFIG.py
@@ -2,8 +2,8 @@
 import os.path
 
 
-ACME_SERVER = "letsencrypt-demo.org"
-"""CA hostname.
+ACME_SERVER = "letsencrypt-demo.org:443"
+"""CA hostname (and optionally :port).
 
 If you create your own server... change this line
 
diff --git a/letsencrypt/client/client.py b/letsencrypt/client/client.py
index 763178d19..9ecaf1b35 100644
--- a/letsencrypt/client/client.py
+++ b/letsencrypt/client/client.py
@@ -59,7 +59,6 @@ class Client(object):
         :type dv_auth: :class:`letsencrypt.client.interfaces.IAuthenticator`
 
         """
-        sanity_check_names([server])
         self.network = network.Network(server)
         self.authkey = authkey
 
diff --git a/letsencrypt/client/network.py b/letsencrypt/client/network.py
index 135349c41..2ec93136d 100644
--- a/letsencrypt/client/network.py
+++ b/letsencrypt/client/network.py
@@ -17,13 +17,16 @@ logging.getLogger("requests").setLevel(logging.WARNING)
 class Network(object):
     """Class for communicating with ACME servers.
 
-    :ivar str server: Certificate authority server
-    :ivar str server_url: Full URL of the CSR server
+    :ivar str server_url: Full URL of the ACME service
 
     """
     def __init__(self, server):
-        self.server = server
-        self.server_url = "https://%s/acme/" % self.server
+        """Initialize Network instance.
+
+        :param str server: ACME (CA) server[:port]
+
+        """
+        self.server_url = "https://%s/acme/" % server
 
     def send(self, msg):
         """Send ACME message to server.
diff --git a/letsencrypt/scripts/main.py b/letsencrypt/scripts/main.py
index 1d7acda97..700c75858 100755
--- a/letsencrypt/scripts/main.py
+++ b/letsencrypt/scripts/main.py
@@ -30,7 +30,8 @@ def main():
     parser.add_argument("-d", "--domains", dest="domains", metavar="DOMAIN",
                         nargs="+")
     parser.add_argument("-s", "--server", dest="server",
-                        help="The ACME CA server address.")
+                        default=CONFIG.ACME_SERVER,
+                        help="The ACME CA server. [%(default)s]")
     parser.add_argument("-p", "--privkey", dest="privkey", type=read_file,
                         help="Path to the private key file for certificate "
                              "generation.")
@@ -75,10 +76,9 @@ def main():
     zope.component.provideUtility(displayer)
 
     installer = determine_installer()
-    server = CONFIG.ACME_SERVER if args.server is None else args.server
 
     if args.revoke:
-        revoc = revoker.Revoker(server, installer)
+        revoc = revoker.Revoker(args.server, installer)
         revoc.list_certs_keys()
         sys.exit()
 
@@ -107,7 +107,7 @@ def main():
     else:
         privkey = client.Client.Key(args.privkey[0], args.privkey[1])
 
-    acme = client.Client(server, privkey, auth, installer)
+    acme = client.Client(args.server, privkey, auth, installer)
 
     # Validate the key and csr
     client.validate_key_csr(privkey)