diff -ur mailx-12.5.orig/mailx.1 mailx-12.5/mailx.1
--- mailx-12.5.orig/mailx.1	2014-06-13 16:28:18.272418000 +0200
+++ mailx-12.5/mailx.1	2014-06-13 16:32:06.757714403 +0200
@@ -219,6 +219,14 @@
 assigns
 .I value
 to it.
+Note, that when setting
+.I from
+variable, domain name of host is automatically added if value does not contain any.
+If you want to enter
+.I from
+address with owner's name, you can use, for example, following format:
+.B -S
+.I \(dqfrom=System User <DoNotReply>\(dq
 .TP
 .BI \-T \ name
 Writes the `Message-Id:' and `Article-Id:' header fields
@@ -2189,7 +2197,8 @@
 as part of the environment
 (this is not restricted to specific variables as in the POSIX standard).
 A value given in a startup file overrides
-a value imported from the environment.
+a value imported from the environment, but it is not possible to unset
+an environment variable in a startup file.
 Options may be either binary,
 in which case it is only significant
 to see whether they are set or not;