Updated Formatter.formatTime documentation.
diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst
index 76633db..20cd57c 100644
--- a/Doc/library/logging.rst
+++ b/Doc/library/logging.rst
@@ -453,6 +453,13 @@
       record. Otherwise, the ISO8601 format is used.  The resulting string is
       returned.
 
+      This function uses a user-configurable function to convert the creation
+      time to a tuple. By default, :func:`time.localtime` is used; to change
+      this for a particular formatter instance, set the ``converter`` attribute
+      to a function with the same signature as :func:`time.localtime` or
+      :func:`time.gmtime`. To change it for all formatters, for example if you
+      want all logging times to be shown in GMT, set the ``converter``
+      attribute in the ``Formatter`` class.
 
    .. method:: formatException(exc_info)