diff --git a/cyruslib.py b/cyruslib.py
--- a/cyruslib.py
+++ b/cyruslib.py
@@ -848,7 +848,7 @@
         concat_items = []
         for item in data:
             if isinstance(item, tuple):
-                item = ' '.join([str(x) for x in item])
+                item = (' '.join([str(x) for x in item])).encode('utf-8')
 
             if len(concat_items) > 0:
                 concat_items.append(item)
@@ -871,7 +871,7 @@
             tokens = tokenize(annotation)
             folder = tokens[0]
 
-            if folder != mailbox:
+            if mailbox != b'*' and folder != mailbox:
                 quoted_mailbox = "\"%s\"" % (mailbox)
                 if folder != quoted_mailbox:
                     # print("mismatch")
diff --git a/pykolab/imap/__init__.py b/pykolab/imap/__init__.py
--- a/pykolab/imap/__init__.py
+++ b/pykolab/imap/__init__.py
@@ -305,13 +305,13 @@
     def folder_quote(self, folder):
         return u'"' + str(folder).strip('"') + '"'
 
-    def get_metadata(self, folder):
+    def get_metadata(self, folder, pattern='*'):
         """
             Obtain all metadata entries on a folder
         """
         metadata = {}
 
-        _metadata = self.imap.getmetadata(self.folder_utf7(folder), '*')
+        _metadata = self.imap.getmetadata(self.folder_utf7(folder), pattern)
 
         for (k, v) in _metadata.items():
             metadata[self.folder_utf8(k)] = v
diff --git a/wallace/module_invitationpolicy.py b/wallace/module_invitationpolicy.py
--- a/wallace/module_invitationpolicy.py
+++ b/wallace/module_invitationpolicy.py
@@ -807,7 +807,7 @@
     if not imap_proxy_auth(user_rec):
         return result
 
-    folders = imap.get_metadata('*')
+    folders = imap.get_metadata('*', FOLDER_TYPE_ANNOTATION)
 
     log.debug(
         _("List %r folders for user %r: %r") % (
@@ -820,16 +820,17 @@
 
     (ns_personal, ns_other, ns_shared) = imap.namespaces()
 
+    _type = _type.encode('utf-8')
     _folders = {}
 
     # Filter the folders by type relevance
     for folder, metadata in folders.items():
-        key = '/shared' + FOLDER_TYPE_ANNOTATION
+        key = ('/shared' + FOLDER_TYPE_ANNOTATION).encode('utf-8')
         if key in metadata:
             if metadata[key].startswith(_type):
                 _folders[folder] = metadata
 
-        key = '/private' + FOLDER_TYPE_ANNOTATION
+        key = ('/private' + FOLDER_TYPE_ANNOTATION).encode('utf-8')
         if key in metadata:
             if metadata[key].startswith(_type):
                 _folders[folder] = metadata
@@ -857,29 +858,29 @@
             if len([_ns for _ns in ns_shared if folder.startswith(_ns)]) > 0:
                 continue
 
-        key = '/shared' + FOLDER_TYPE_ANNOTATION
+        key = ('/shared' + FOLDER_TYPE_ANNOTATION).encode('utf-8')
         if key in metadata:
             if metadata[key].startswith(_type):
                 result.append(folder)
 
-        key = '/private' + FOLDER_TYPE_ANNOTATION
+        key = ('/private' + FOLDER_TYPE_ANNOTATION).encode('utf-8')
         if key in metadata:
             if metadata[key].startswith(_type):
                 result.append(folder)
 
             # store default folder in user record
-            if metadata[key].endswith('.default'):
+            if metadata[key].endswith(b'.default'):
                 user_rec['_default_folder'] = folder
                 continue
 
             # store private and confidential folders in user record
-            if metadata[key].endswith('.confidential'):
+            if metadata[key].endswith(b'.confidential'):
                 if '_confidential_folder' not in user_rec:
                     user_rec['_confidential_folder'] = folder
 
                 continue
 
-            if metadata[key].endswith('.private'):
+            if metadata[key].endswith(b'.private'):
                 if '_private_folder' not in user_rec:
                     user_rec['_private_folder'] = folder
 
@@ -1123,7 +1124,7 @@
             imap.folder_utf7(targetfolder),
             None,
             None,
-            saveobj.to_message(creator="Kolab Server <wallace@localhost>").as_string()
+            saveobj.to_message(creator="Kolab Server <wallace@localhost>").as_string().encode('utf-8')
         )
         return result