diff -r 68716caa7745 -r 3f2e25dc99ab src/Pure/General/exn.scala
--- a/src/Pure/General/exn.scala	Sat Jan 09 23:22:24 2010 +0100
+++ b/src/Pure/General/exn.scala	Sat Jan 09 23:22:56 2010 +0100
@@ -17,7 +17,7 @@
 
   def capture[A](e: => A): Result[A] =
     try { Res(e) }
-    catch { case exn: RuntimeException => Exn[A](exn) }
+    catch { case exn: RuntimeException => Exn[A](exn) }   // FIXME *all* exceptions (!?), cf. ML version
 
   def release[A](result: Result[A]): A =
     result match {