diff --git a/src/irclib.py b/src/irclib.py
index 9d9161f6e..45b302823 100644
--- a/src/irclib.py
+++ b/src/irclib.py
@@ -1040,7 +1040,7 @@ class Irc(IrcCommandDispatcher):
                  self.network, caps)
         self.state.capabilities_ack.update(caps)
 
-        if 'sasl' in caps:
+        if 'sasl' in caps and self.sasl:
             self.sendMsg(ircmsgs.IrcMsg(command='AUTHENTICATE', args=(self.sasl.upper(),)))
         else:
             self.sendMsg(ircmsgs.IrcMsg(command='CAP', args=('END',)))