dummy driver

[Krister Pettersen <kristerp broadpark no>]

When i try to enable the dummy driver as explained at
http://gnome.org/learn/access-guide/2.10/access-guide.html#sysadmin-49,
i get this error:
XFree86 Version 4.3.0.1 (Debian 4.3.0.dfsg.1-14 20050601051219
fabbione fabbione net)
Release Date: 15 August 2003
X Protocol Version 11, Revision 0, Release 6.6
Build Operating System: Linux 2.4.29-pre2 i686 [ELF] 
Build Date: 01 June 2005

This version of XFree86 has been extensively modified by the Debian
Project, and is not supported by the XFree86 Project, Inc., in any
way.  Bugs should be reported to the Debian Bug Tracking System; see
<URL: http://www.debian.org/Bugs/Reporting >.

We strongly encourage the use of the "reportbug" package and command
to ensure that bug reports contain as much useful information as
possible.

Before filing a bug report, you may want to consult the Debian X FAQ:
       XHTML version: file:///usr/share/doc/xfree86-common/FAQ.xhtml
  plain text version: file:///usr/share/doc/xfree86-common/FAQ.gz

Module Loader present
OS Kernel: Linux version 2.6.8-2-686 (horms tabatha lab ultramonkey org)
(gcc version 3.3.5 (Debian 1:3.3.5-12)) #1 Thu May 19 17:53:30 JST 2005 
Markers: (--) probed, (**) from config file, (==) default setting,
         (++) from command line, (!!) notice, (II) informational,
         (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/XFree86.0.log", Time: Fri Jun 10 03:11:46 2005
(==) Using config file: "/etc/X11/XF86Config-4"
Data incomplete in file /etc/X11/XF86Config-4
	Undefined Screen "Screen[0]" referenced by ServerLayout "Default
Layout".
(EE) Problem parsing the config file
(EE) Error from xf86HandleConfigFile()

Fatal server error:
no screens found

When reporting a problem related to a server crash, please send
the full server output, not just the last messages.
This can be found in the log file "/var/log/XFree86.0.log".
Please report problems to submit bugs debian org