diff -Naur MPlayer-1.0pre5.orig/DOCS/tech/slave.txt MPlayer-1.0pre5/DOCS/tech/slave.txt
--- MPlayer-1.0pre5.orig/DOCS/tech/slave.txt	2004-09-01 17:15:36.000000000 +0200
+++ MPlayer-1.0pre5/DOCS/tech/slave.txt	2004-09-03 03:19:10.511849032 +0200
@@ -90,6 +90,10 @@
 	Toggle stay-on-top. Supported by drivers which use X11, except SDL,
 	as well as directx and gl2 under Windows.
 
+switch_vsync [<value>]
+    Toggle vsync (1 == on, 0 == off). If no value is provided,
+    vsync status is inverted.
+
 panscan <value> [value2]
     ???