diff -r b23c42b9f78a -r 2cb7e34f6096 src/Pure/System/session.scala
--- a/src/Pure/System/session.scala	Fri Nov 25 16:32:29 2011 +0100
+++ b/src/Pure/System/session.scala	Fri Nov 25 18:37:14 2011 +0100
@@ -455,7 +455,7 @@
             case result: Isabelle_Process.Result =>
               handle_result(result)
               if (result.is_syslog) syslog_messages.event(result)
-              if (result.is_stdout) raw_output_messages.event(result)
+              if (result.is_stdout || result.is_stderr) raw_output_messages.event(result)
               raw_messages.event(result)
           }