diff --git a/scrapy/logformatter.py b/scrapy/logformatter.py
index 2a89c00c5..075a6d862 100644
--- a/scrapy/logformatter.py
+++ b/scrapy/logformatter.py
@@ -43,6 +43,7 @@ class LogFormatter(object):
                 'request_flags' : request_flags,
                 'referer': referer_str(request),
                 'response_flags': response_flags,
+                # backward compatibility with Scrapy logformatter below 1.4 version
                 'flags': response_flags
             }
         }
diff --git a/tests/test_logformatter.py b/tests/test_logformatter.py
index 52646ec1b..94e6c9fde 100644
--- a/tests/test_logformatter.py
+++ b/tests/test_logformatter.py
@@ -66,7 +66,6 @@ class LoggingContribTest(unittest.TestCase):
 
 
 class LogFormatterSubclass(LogFormatter):
-    # Formatter with format spec that is same as in Scrapy before 1.3 version.
     def crawled(self, request, response, spider):
         kwargs = super(LogFormatterSubclass, self).crawled(
         request, response, spider)
@@ -82,7 +81,6 @@ class LogFormatterSubclass(LogFormatter):
 
 
 class LogformatterSubclassTest(LoggingContribTest):
-    # Test if old crawledmsg format string still works fine
     def setUp(self):
         self.formatter = LogFormatterSubclass()
         self.spider = Spider('default')