Misc. clarifications added per Alan Kennedy's report on his

experiences implementing WSGI in Jython/Java Servlets.

pep-0333.txt

@@ -363,8 +363,18 @@ Variable               Value
                        preference.)
 
 ``wsgi.errors``        An output stream to which error output can be
-                       written.  For most servers, this will be the
-                       server's error log.
+                       written, for the purpose of recording program
+                       or other errors in a standardized and possibly
+                       centralized location.  For many servers, this
+                       will be the server's main error log.
+
+                       Alternatively, this may be ``sys.stderr``, or 
+                       a log file of  some sort.  The server's
+                       documentation should include an explanation of
+                       how to configure this or where to find the
+                       recorded output.  A server or gateway may
+                       supply different error streams to different
+                       applications, if this is desired.
 
 ``wsgi.multithread``   This value should be true if the application
                        object may be simultaneously invoked by another
@@ -514,7 +524,12 @@ The ``write()`` Callable
 
 The return value of the ``start_response()`` callable is a
 one-argument `write()`` callable, that accepts strings to write as
-part of the HTTP response body.
+part of the HTTP response body.  The server or gateway must
+not modify supplied strings in any way; they must be treated
+as binary byte sequences with no character interpretation, line
+ending changes, or other modification.  The application is responsible
+for ensuring that the string(s) to be written are in a format suitable
+for the client.
 
 Note that the purpose of the ``write()`` callable is primarily to
 support existing application frameworks that support a streaming