===================================================================
RCS file: /cvs/mandoc/mdoc.7,v
retrieving revision 1.169
retrieving revision 1.170
diff -u -p -r1.169 -r1.170
--- mandoc/mdoc.7	2010/12/06 16:37:32	1.169
+++ mandoc/mdoc.7	2010/12/18 19:12:00	1.170
@@ -1,4 +1,4 @@
-.\"	$Id: mdoc.7,v 1.169 2010/12/06 16:37:32 kristaps Exp $
+.\"	$Id: mdoc.7,v 1.170 2010/12/18 19:12:00 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: December 6 2010 $
+.Dd $Mdocdate: December 18 2010 $
 .Dt MDOC 7
 .Os
 .Sh NAME
@@ -2665,9 +2665,13 @@ and
 Close a scope opened by
 .Sx \&Xo .
 .Ss \&Xo
-Open an extension scope.
-This macro originally existed to extend the 9-argument limit of troff;
-since this limit has been lifted, the macro has been deprecated.
+Extend the header of an
+.Sx \&It
+macro or the body of a partial-implicit block macro
+beyond the end of the input line.
+This macro originally existed to work around the 9-argument limit
+of historic
+.Xr roff 7 .
 .Ss \&Xr
 Link to another manual
 .Pq Qq cross-reference .