diff --git a/slixmpp/clientxmpp.py b/slixmpp/clientxmpp.py
index add7f437..66a846d3 100644
--- a/slixmpp/clientxmpp.py
+++ b/slixmpp/clientxmpp.py
@@ -188,9 +188,6 @@ class ClientXMPP(BaseXMPP):
                              ``'none'``. If set to ``'remove'``,
                              the entry will be deleted.
         :param groups: The roster groups that contain this item.
-        :param block: Specify if the roster request will block
-                      until a response is received, or a timeout
-                      occurs. Defaults to ``True``.
         :param timeout: The length of time (in seconds) to wait
                         for a response before continuing if blocking
                         is used. Defaults to
@@ -205,12 +202,11 @@ class ClientXMPP(BaseXMPP):
         subscription = kwargs.get('subscription', current['subscription'])
         groups = kwargs.get('groups', current['groups'])
 
-        block = kwargs.get('block', True)
         timeout = kwargs.get('timeout', None)
         callback = kwargs.get('callback', None)
 
         return self.client_roster.update(jid, name, subscription, groups,
-                                         block, timeout, callback)
+                                         timeout, callback)
 
     def del_roster_item(self, jid):
         """Remove an item from the roster.
diff --git a/slixmpp/plugins/xep_0280/carbons.py b/slixmpp/plugins/xep_0280/carbons.py
index 15b07229..a64ccbfd 100644
--- a/slixmpp/plugins/xep_0280/carbons.py
+++ b/slixmpp/plugins/xep_0280/carbons.py
@@ -66,16 +66,20 @@ class XEP_0280(BasePlugin):
     def _handle_carbon_sent(self, msg):
         self.xmpp.event('carbon_sent', msg)
 
-    def enable(self, ifrom=None, block=True, timeout=None, callback=None):
+    def enable(self, ifrom=None, timeout=None, callback=None,
+               timeout_callback=None):
         iq = self.xmpp.Iq()
         iq['type'] = 'set'
         iq['from'] = ifrom
         iq.enable('carbon_enable')
-        return iq.send(block=block, timeout=timeout, callback=callback)
+        return iq.send(timeout_callback=timeout_callback, timeout=timeout,
+                       callback=callback)
 
-    def disable(self, ifrom=None, block=True, timeout=None, callback=None):
+    def disable(self, ifrom=None, timeout=None, callback=None,
+                timeout_callback=None):
         iq = self.xmpp.Iq()
         iq['type'] = 'set'
         iq['from'] = ifrom
         iq.enable('carbon_disable')
-        return iq.send(block=block, timeout=timeout, callback=callback)
+        return iq.send(timeout_callback=timeout_callback, timeout=timeout,
+                       callback=callback)
diff --git a/slixmpp/roster/single.py b/slixmpp/roster/single.py
index 07a1f188..a37e3eb7 100644
--- a/slixmpp/roster/single.py
+++ b/slixmpp/roster/single.py
@@ -238,7 +238,7 @@ class RosterNode(object):
             return self.update(jid, subscription='remove')
 
     def update(self, jid, name=None, subscription=None, groups=[],
-                     block=True, timeout=None, callback=None):
+                     timeout=None, callback=None, timeout_callback=None):
         """
         Update a JID's subscription information.
 
@@ -248,15 +248,11 @@ class RosterNode(object):
             subscription -- The subscription state. May be one of: 'to',
                             'from', 'both', 'none', or 'remove'.
             groups       -- A list of group names.
-            block        -- Specify if the roster request will block
-                            until a response is received, or a timeout
-                            occurs. Defaults to True.
             timeout      -- The length of time (in seconds) to wait
                             for a response before continuing if blocking
                             is used. Defaults to self.response_timeout.
             callback     -- Optional reference to a stream handler function.
                             Will be executed when the roster is received.
-                            Implies block=False.
         """
         self[jid]['name'] = name
         self[jid]['groups'] = groups
@@ -269,7 +265,8 @@ class RosterNode(object):
                                            'subscription': subscription,
                                            'groups': groups}}
 
-            return iq.send(block, timeout, callback)
+            return iq.send(timeout=timeout, callback=callback,
+                           timeout_callback=timeout_callback)
 
     def presence(self, jid, resource=None):
         """