diff --git a/DOCS/mplayer.1 b/DOCS/mplayer.1
index 79bc276f14..dbdfa73e25 100644
--- a/DOCS/mplayer.1
+++ b/DOCS/mplayer.1
@@ -2672,7 +2672,7 @@ encode to MP3 (using Lame)
 .PD 1
 .
 .TP
-.B \-of <format>
+.B \-of <format> (BETA CODE!)
 Encode to the specified format.
 Use \-of help to get a list of available formats.