diff --git a/share/man/man4/md.4 b/share/man/man4/md.4
index cac7cf594431..911037f8ab57 100644
--- a/share/man/man4/md.4
+++ b/share/man/man4/md.4
@@ -1,4 +1,4 @@
-.\"   $NetBSD: md.4,v 1.2 1999/03/16 01:19:16 garbled Exp $
+.\"   $NetBSD: md.4,v 1.3 2004/01/12 20:03:39 is Exp $
 .\"
 .\" This file is in the public domain.
 .\"
@@ -19,6 +19,13 @@ Memory for the disk must be allocated within the kernel or with
 before the
 .Nm
 device may be used as a disk.
+Its behaviour is configured by the kernel options
+.Sy MEMORY_DISK_HOOKS,
+.Sy MEMORY_DISK_IS_ROOT,
+.Sy MEMORY_DISK_ROOT_SIZE, 
+.Sy MEMORY_DISK_DYNAMIC
+and
+.Sy MEMORY_DISK_SERVER .
 .Sh FILES
 .Bl -tag -width /dev/rmdX -compact
 .It Pa "/dev/md??"
@@ -28,4 +35,5 @@ raw mode memory disk devices.
 .El
 .Sh SEE ALSO
 .Xr mdconfig 8 ,
-.Xr mdsetimage 8
+.Xr mdsetimage 8 ,
+.Xr options 4
diff --git a/share/man/man4/options.4 b/share/man/man4/options.4
index 38ada534ff6f..8bf7b9e57b0c 100644
--- a/share/man/man4/options.4
+++ b/share/man/man4/options.4
@@ -1,4 +1,4 @@
-.\"	$NetBSD: options.4,v 1.225 2003/11/20 15:07:07 wiz Exp $
+.\"	$NetBSD: options.4,v 1.226 2004/01/12 20:03:39 is Exp $
 .\"
 .\" Copyright (c) 1996
 .\" 	Perry E. Metzger.  All rights reserved.
@@ -971,6 +971,11 @@ See also
 .Xr sysctl 8
 and
 .Xr sysctl 3 .
+.It Cd options MEMORY_DISK_DYNAMIC
+This options makes the
+.Xr md 4 
+.Tn RAM
+disk size dynamically sized.
 .It Cd options MEMORY_DISK_HOOKS
 This option allows for some machine dependent functions to be called when
 the
@@ -993,6 +998,10 @@ Allocates the given number of 512 byte blocks as memory for the
 .Tn RAM
 disk, to be populated with
 .Xr mdsetimage 8 .
+.It Cd options MEMORY_DISK_SERVER=0
+Do not include the interface to a userland memory disk server process.
+Per default, this options is set to 1, including the support code. 
+Useful for install media kernels.
 .It Cd options VNODE_OP_NOINLINE
 Do not inline the
 .Fn VOP_*