src/Pure/System/isabelle_process.scala

--- a/src/Pure/System/isabelle_process.scala	Fri May 02 19:51:40 2014 +0200
+++ b/src/Pure/System/isabelle_process.scala	Fri May 02 20:01:45 2014 +0200
@@ -12,7 +12,7 @@
 
 
 class Isabelle_Process(
-  receiver: Prover.Message => Unit = System.out.println(_),
+  receiver: Prover.Message => Unit = Console.println(_),
   prover_args: List[String] = Nil)
 {
   /* text and tree data */