diff --git a/ChangeLog b/ChangeLog
index 07a32b0ec..5d8e9cf1a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+	* Added conf.supybot.plugins.Karma.allowSelfRating, which determines
+	whether users are allowed to adjust the karma of their current nick.
+
 	* Added --nolimit option to Misc.last, which causes it to return all
 	matches that are in the history.
 
diff --git a/plugins/Karma.py b/plugins/Karma.py
index bb7812c1c..159dce2fe 100644
--- a/plugins/Karma.py
+++ b/plugins/Karma.py
@@ -66,6 +66,9 @@ conf.registerChannelValue(conf.supybot.plugins.Karma, 'rankingDisplay',
 conf.registerChannelValue(conf.supybot.plugins.Karma, 'mostDisplay',
     registry.Integer(25, """Determines how many karma things are shown when
     the most command is called.'"""))
+conf.registerChannelValue(conf.supybot.plugins.Karma, 'allowSelfRating',
+    registry.Boolean(False, """Determines whether users can adjust the karma
+    of their nick."""))
 
 class Karma(callbacks.PrivmsgCommandAndRegexp, plugins.ChannelDBHandler):
     addressedRegexps = ['increaseKarma', 'decreaseKarma']
@@ -215,11 +218,14 @@ class Karma(callbacks.PrivmsgCommandAndRegexp, plugins.ChannelDBHandler):
                 irc.error('I have no karma for this channel.')
         except KeyError:
             raise callbacks.ArgumentError
-        
+
     def increaseKarma(self, irc, msg, match):
         r"^(\S+)\+\+(|\s+)$"
         name = match.group(1)
         normalized = name.lower()
+        if not self.registryValue('allowSelfRating', msg.args[0]):
+            if normalized == msg.nick.lower():
+                return
         db = self.getDb(msg.args[0])
         cursor = db.cursor()
         cursor.execute("""INSERT INTO karma VALUES (NULL, %s, %s, 0, 0)""",
@@ -234,6 +240,9 @@ class Karma(callbacks.PrivmsgCommandAndRegexp, plugins.ChannelDBHandler):
         r"^(\S+)--(|\s+)$"
         name = match.group(1)
         normalized = name.lower()
+        if not self.registryValue('allowSelfRating', msg.args[0]):
+            if normalized == msg.nick.lower():
+                return
         db = self.getDb(msg.args[0])
         cursor = db.cursor()
         cursor.execute("""INSERT INTO karma VALUES (NULL, %s, %s, 0, 0)""",
diff --git a/test/test_Karma.py b/test/test_Karma.py
index 9feb28b66..7347bf010 100644
--- a/test/test_Karma.py
+++ b/test/test_Karma.py
@@ -99,7 +99,6 @@ if sqlite is not None:
             finally:
                 conf.supybot.plugins.Karma.response.setValue(orig)
                 conf.supybot.plugins.Karma.rankingDisplay.setValue(original)
-                
 
         def testMost(self):
             self.assertError('most increased')
@@ -133,6 +132,21 @@ if sqlite is not None:
             finally:
                 conf.supybot.plugins.Karma.simpleOutput.setValue(orig)
 
+        def testSelfRating(self):
+            nick = self.nick
+            try:
+                orig = conf.supybot.plugins.Karma.allowSelfRating()
+                conf.supybot.plugins.Karma.allowSelfRating.setValue(False)
+                self.assertNoResponse('%s++' % nick, 2)
+                self.assertResponse('karma %s' % nick,
+                                    '%s has no karma.' % nick)
+                conf.supybot.plugins.Karma.allowSelfRating.setValue(True)
+                self.assertNoResponse('%s++' % nick, 2)
+                self.assertRegexp('karma %s' % nick,
+                              'Karma for \'%s\'.*increased 1.*total.*1' % nick)
+            finally:
+                conf.supybot.plugins.Karma.allowSelfRating.setValue(orig)
+
         def testKarmaOutputConfigurable(self):
             self.assertNoResponse('foo++', 2)
             try:
@@ -160,11 +174,11 @@ if sqlite is not None:
                 self.assertRegexp('karma most active', 'bar')
             finally:
                 conf.supybot.plugins.Karma.mostDisplay.setValue(orig)
-                
+
 
         def testIncreaseKarmaWithNickNotCallingInvalidCommand(self):
             self.assertNoResponse('%s: foo++' % self.irc.nick, 3)
-        
+
 
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