Update logger usage information.
diff --git a/docs/busybox.sgml b/docs/busybox.sgml
index c64dab8..62ef4e3 100644
--- a/docs/busybox.sgml
+++ b/docs/busybox.sgml
@@ -1872,7 +1872,7 @@
 		</para>
 
 		<para>
-		Write MESSAGE to the system log.  If MESSAGE is '-', log
+		Write MESSAGE to the system log.  If MESSAGE is omitted, log
 		stdin.
 		</para>