diff --git a/src/ircmsgs.py b/src/ircmsgs.py
index ee5f5286a..df6a70872 100644
--- a/src/ircmsgs.py
+++ b/src/ircmsgs.py
@@ -210,9 +210,11 @@ class IrcMsg(object):
 
 def isAction(msg):
     """A predicate returning true if the PRIVMSG in question is an ACTION"""
-    return msg.command == 'PRIVMSG' and \
-           msg.args[1].startswith('\x01ACTION') and \
-           msg.args[1].endswith('\x01')
+    if msg.command == 'PRIVMSG' and msg.args[1].endswith('\x01'):
+        L = msg.args[1].split(None, 1)
+        return len(L) == 2 and L[0] == '\x01ACTION'
+    else:
+        return False
 
 _unactionre = re.compile(r'^\x01ACTION (.*)\x01$')
 def unAction(msg):
diff --git a/test/test_ircmsgs.py b/test/test_ircmsgs.py
index be5059894..36b639e1c 100644
--- a/test/test_ircmsgs.py
+++ b/test/test_ircmsgs.py
@@ -129,6 +129,10 @@ class FunctionsTestCase(unittest.TestCase):
         for msg in msgs:
             self.failUnless(ircmsgs.isAction(msg))
 
+    def testIsActionFalseWhenNoSpaces(self):
+        msg = ircmsgs.IrcMsg('PRIVMSG #foo :\x01ACTIONfoobar\x01')
+        self.failIf(ircmsgs.isAction(msg))
+
     def testUnAction(self):
         s = 'foo bar baz'
         msg = ircmsgs.action('#foo', s)