diff --git a/bootfiles/20b/boot-2010-11-1-cross.lisp b/bootfiles/20b/boot-2010-11-1-cross.lisp
index 7bac0ca907febea2adab3f3d7f14628b2187e1bf..b387c700aa2fdfe48364b343e57c45ef9face5ad 100644
--- a/bootfiles/20b/boot-2010-11-1-cross.lisp
+++ b/bootfiles/20b/boot-2010-11-1-cross.lisp
@@ -1,4 +1,5 @@
-;;; Adding slots to the backend requires a cross-compile.
+;;; Bootstrap for building the 2010-12 snapshot.  Adding slots to the
+;;; backend requires a cross-compile.
 ;;;
 ;;; Answer CLOBBER-IT for the restart about changing the size of the
 ;;; backend structure.