diff --git a/radicale/acl/PAM.py b/radicale/acl/PAM.py
index 7cb19d9..d7d021b 100644
--- a/radicale/acl/PAM.py
+++ b/radicale/acl/PAM.py
@@ -19,7 +19,7 @@
 """
 PAM ACL.
 
-Authentication based on the ``python-pam`` module
+Authentication based on the ``pam-python`` module.
 
 """
 
@@ -29,7 +29,7 @@ import pwd
 from radicale import acl, config, log
 
 
-GROUP_MEMBERSHIP = config.get("acl", "group_membership")
+GROUP_MEMBERSHIP = config.get("acl", "pam_group_membership")
 
 
 def has_right(owner, user, password):
@@ -37,26 +37,40 @@ def has_right(owner, user, password):
     if not user or (owner not in acl.PRIVATE_USERS and user != owner):
         # No user given, or owner is not private and is not user, forbidden
         return False
-    
-    try: # 1 - Does the user exist in the PAM system?
-      pwd.getpwnam(user).pw_uid
-      log.LOGGER.debug("User %s found" % user)
-    except KeyError: # No such user in the PAM system
-      log.LOGGER.debug("User %s not found" % user)
-      return False
-    
-    try: # 2 - Does the user belong to the required group?
-      for member in grp.getgrnam(GROUP_MEMBERSHIP):
-	if member == user:
-	  raise Exception()
-      log.LOGGER.debug("The user doesn't belong to the required group (%s)" % GROUP_MEMBERSHIP)
-      return False
+
+    # Check whether the user exists in the PAM system
+    try:
+        pwd.getpwnam(user).pw_uid
     except KeyError:
-      log.LOGGER.debug("The membership required group (%s) doesn't exist" % GROUP_MEMBERSHIP)
-      return False
-    except Exception:
-      log.LOGGER.debug("The user belong to the required group (%s)" % GROUP_MEMBERSHIP)
-        
-    if pam.authenticate(user, password): # 3 - Does the password match ?
-      return True
-    return False # Authentication failled
+        log.LOGGER.debug("User %s not found" % user)
+        return False
+    else:
+        log.LOGGER.debug("User %s found" % user)
+
+    # Check whether the group exists
+    try:
+        members = grp.getgrnam(GROUP_MEMBERSHIP)
+    except KeyError:
+        log.LOGGER.debug(
+            "The PAM membership required group (%s) doesn't exist" %
+            GROUP_MEMBERSHIP)
+        return False
+
+    # Check whether the user belongs to the required group
+    for member in members:
+        if member == user:
+            log.LOGGER.debug(
+                "The PAM user belongs to the required group (%s)" %
+                GROUP_MEMBERSHIP)
+            # Check the password
+            if pam.authenticate(user, password):
+                return True
+            else:
+                log.LOGGER.debug("Wrong PAM password")
+            break
+    else:
+        log.LOGGER.debug(
+            "The PAM user doesn't belong to the required group (%s)" %
+            GROUP_MEMBERSHIP)
+
+    return False
diff --git a/radicale/acl/Courier-Authdaemon.py b/radicale/acl/courier.py
similarity index 61%
rename from radicale/acl/Courier-Authdaemon.py
rename to radicale/acl/courier.py
index 3b4260c..a2c2b1f 100644
--- a/radicale/acl/Courier-Authdaemon.py
+++ b/radicale/acl/courier.py
@@ -16,11 +16,17 @@
 # You should have received a copy of the GNU General Public License
 # along with Radicale.  If not, see <http://www.gnu.org/licenses/>.
 
-import socket,os,sys
+"""
+Courier-Authdaemon ACL.
+
+"""
+
+import sys
+import socket
 from radicale import acl, config, log
 
 
-COURIER_SOCKET = config.get("acl", "courier-auth_socket")
+COURIER_SOCKET = config.get("acl", "courier_socket")
 
 
 def has_right(owner, user, password):
@@ -28,21 +34,24 @@ def has_right(owner, user, password):
     if not user or (owner not in acl.PRIVATE_USERS and user != owner):
         # No user given, or owner is not private and is not user, forbidden
         return False
-        
-    line = sys.argv[0] . "\nlogin\n" + user + "\n" + password
-    line = len(line) + "\n" + line
+
+    line = "%s\nlogin\n%s\n%s" % (sys.argv[0], user, password)
+    line = "%i\n%s" % (len(line), line)
     try:
-      s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
-      s.connect(COURIER_SOCKET)
-      log.LOGGER.debug("Sending to socket the request: %s" % line)
-      s.send(line)
-      data = s.recv(1024)
-      s.close()
-    except socket.error, (value,message): 
-      log.LOGGER.debug("Unable to communicate with the socket (error: %s)" % message)
-      return False
-    log.LOGGER.debug("Got socket response: %s" % repr(data))
+        sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        sock.connect(COURIER_SOCKET)
+        log.LOGGER.debug("Sending to Courier socket the request: %s" % line)
+        sock.send(line)
+        data = sock.recv(1024)
+        sock.close()
+    except socket.error, (_, message):
+        log.LOGGER.debug(
+            "Unable to communicate with Courier socket: %s" % message)
+        return False
+
+    log.LOGGER.debug("Got Courier socket response: %r" % data)
+
     if repr(data) == "FAIL":
-      return False
+        return False
+
     return True
-    
\ No newline at end of file