diff --git a/src/irclib.py b/src/irclib.py
index 84fabe710..f9bce6d7f 100644
--- a/src/irclib.py
+++ b/src/irclib.py
@@ -726,6 +726,7 @@ class Irc(IrcCommandDispatcher):
             if len(str(msg)) > 512:
                 # Yes, this violates the contract, but at this point it doesn't
                 # matter.  That's why we gotta go munging in private attributes
+                log.warning('Truncating %r, message is too long.', msg)
                 msg._str = msg._str[:500] + '\r\n'
                 msg._len =  len(str(msg))
             # I don't think we should do this.  Why should it matter?  If it's