diff --git a/plugins/Admin/plugin.py b/plugins/Admin/plugin.py
index f52430c0d..1b518635c 100644
--- a/plugins/Admin/plugin.py
+++ b/plugins/Admin/plugin.py
@@ -355,7 +355,7 @@ class Admin(callbacks.Plugin):
 
         Perform <command> (with associated <arg>s on all channels on current network."""
         for channel in irc.state.channels:
-            msg = ircmsgs.IrcMsg(msg=msg, args=(channel, *msg.args[1:]))
+            msg = ircmsgs.IrcMsg(msg=msg, args=(channel,) + msg.args[1:])
             self.Proxy(irc.getRealIrc(), msg, commandAndArgs)
     acmd = wrap(acmd, ['admin', many('something')])
 
diff --git a/plugins/Admin/test.py b/plugins/Admin/test.py
index 90b8ccc7e..f17b29972 100644
--- a/plugins/Admin/test.py
+++ b/plugins/Admin/test.py
@@ -132,7 +132,7 @@ class AdminTestCase(PluginTestCase):
             msgs.append(msg)
             msg = self.irc.takeMsg()
         self.assertCountEqual(
-            [(msg.command, *msg.args) for msg in msgs],
+            [(msg.command,) + msg.args for msg in msgs],
             [("PRIVMSG", "#foo", "hi #foo"), ("PRIVMSG", "#bar", "hi #bar")])
 
 # vim:set shiftwidth=4 softtabstop=4 expandtab textwidth=79:
diff --git a/plugins/User/plugin.py b/plugins/User/plugin.py
index 2656dc5a0..579906c21 100644
--- a/plugins/User/plugin.py
+++ b/plugins/User/plugin.py
@@ -209,7 +209,14 @@ class User(callbacks.Plugin):
             password>. Obviously this message must be sent to the bot
             privately (not in a channel). If the requesting user is an owner
             user, then <old password> needn't be correct.
+            If the <new password> is "!", password login will be disabled.
             """
+            if password == "!":
+                password = None
+            elif len(password) < 3:
+                irc.error(_('The password must be at least 3 characters long.'),
+                        Raise=True)
+
             try:
                 u = ircdb.users.getUser(msg.prefix)
             except KeyError:
diff --git a/src/irclib.py b/src/irclib.py
index 0ceeff4e7..a74efda3c 100644
--- a/src/irclib.py
+++ b/src/irclib.py
@@ -1973,7 +1973,7 @@ class Irc(IrcCommandDispatcher, log.Firewalled):
 
     def do906(self, msg):
         log.warning('%s: SASL authentication aborted', self.network)
-        self.tryNextSaslMechanism(msg)
+        self.tryNextSaslMechanism(msg)  # TODO: should not try this in state INIT_WAITING_MOTD (set when sending CAP END because of exhausted list of SASL mechs)
 
     def do907(self, msg):
         log.warning('%s: Attempted SASL authentication when we were already '