--- src/bin/date/date.1	2003/06/17 04:22:49	1.2
+++ src/bin/date/date.1	2005/07/20 06:10:51	1.3
@@ -34,7 +34,7 @@
 .\"
 .\"     @(#)date.1	8.3 (Berkeley) 4/28/95
 .\" $FreeBSD: src/bin/date/date.1,v 1.34.2.15 2003/02/24 03:01:00 trhodes Exp $
-.\" $DragonFly: src/bin/date/date.1,v 1.1 2003/06/15 23:44:59 dillon Exp $
+.\" $DragonFly$
 .\"
 .Dd November 17, 1993
 .Dt DATE 1
@@ -220,6 +220,22 @@ When the date is adjusted to a specific
 the resulting timezone will be set so that the date matches the earlier of
 the two times.
 .Pp
+Adjusting the date by months is inherently ambiguous because
+a month is a unit of variable length depending on the current date.
+This kind of date adjustment is applied in the most intuitive way.
+First of all,
+.Nm
+tries to preserve the day of the month.
+If it is impossible because the target month is shorter than the present one,
+the last day of the target month will be the result.
+For example, using
+.Fl v No +1m
+on May 31 will adjust the date to June 30, while using the same option
+on January 30 will result in the date adjusted to the last day of February.
+This approach is also believed to make the most sense for shell scripting.
+Nevertheless, be aware that going forth and back by the same number of
+months may take you to a different date.
+.Pp
 Refer to the examples below for further details.
 .El
 .Pp
@@ -296,6 +312,12 @@ will display the last day of February in
 .Pp
 .Dl "Tue Feb 29 03:18:00 GMT 2000"
 .Pp
+So will do the command:
+.Pp
+.Dl "date -v30d -v3m -v0y -v-1m"
+.Pp
+because there is no such date as the 30th of February.
+.Pp
 The command:
 .Pp
 .Dl "date -v1d -v+1m -v-1d -v-fri"