diff -r 81f8ff2a9bf2 -r 1d0bfa4c75c0 mercurial/commands.py
--- a/mercurial/commands.py	Wed Jul 25 15:58:10 2007 +0900
+++ b/mercurial/commands.py	Thu Jul 26 07:56:04 2007 -0400
@@ -2916,6 +2916,8 @@
            _('ignore changes in the amount of white space')),
           ('B', 'ignore-blank-lines', None,
            _('ignore changes whose lines are all blank')),
+          ('U', 'unified', 3,
+           _('number of lines of context to show'))
          ] + walkopts,
          _('hg diff [OPTION]... [-r REV1 [-r REV2]] [FILE]...')),
     "^export":