diff --git a/runtime/doc/vimtutor.1 b/runtime/doc/vimtutor.1
index 0aa7e8d..ec2d85a 100644
--- a/runtime/doc/vimtutor.1
+++ b/runtime/doc/vimtutor.1
@@ -47,7 +47,7 @@
 was originally written for Vi by Michael C. Pierce and Robert K. Ware,
 Colorado School of Mines using ideas supplied by Charles Smith,
 Colorado State University.
-E-mail: bware@mines.colorado.edu.
+E-mail: bware@mines.colorado.edu (now invalid).
 .br
 It was modified for
 .B Vim