NEWS

--- a/NEWS	Thu Dec 12 22:38:25 2013 +0100
+++ b/NEWS	Thu Dec 12 22:56:28 2013 +0100
@@ -12,6 +12,10 @@
 * Document antiquotation @{file_unchecked} is like @{file}, but does
 not check existence within the file-system.
 
+* Discontinued legacy_isub_isup, which was a temporary Isabelle/ML
+workaround in Isabelle2013-1.  The prover process no longer accepts
+old identifier syntax with \<^isub> or \<^isup>.
+
 
 *** Prover IDE -- Isabelle/Scala/jEdit ***