Hi,
Take a look into the web.xml in the standalone dist.
You can configure a missing-auth-mapping Param for the WebDav Servlet.
<init-param>
<param-name>missing-auth-mapping</param-name>
<param-value>admin:admin</param-value>
<description>
Defines how a missing authorization header should be handled.
1) If this init-param is missing, a 401 response is generated.
This is suiteable for clients (eg. webdav clients) for which
sending a proper authorization header is not possible if the
server never sent a 401.
2) If this init-param is present with an empty value,
null-credentials are returned, thus forcing an null login
on the repository.
3) If this init-param is present with the value
'guestcredentials'
java.jcr.GuestCredentials are used to login to the
repository.
4) If this init-param has a 'user:password' value, the
respective
simple credentials are generated.
</description>
</init-param>
greets
claus