verification of user id '' not configured

[Enrique Porta]

Hi! i have an apache 2.2.15 server and i want to configure a secure folder.

This is my secure configuration

<Location /svn/>
    DAV svn
    SVNParentPath /var/lib/svn
    SVNListParentPath On

    AuthType Digest
    AuthName "Private"
    AuthUserFile /etc/svn-auth-file
    AuthzSVNAccessFile /etc/svn-authz-file
    Require valid-user
 </Location>

The svn-auth-file are create wit the htdigest command and the "Private" realm .

The content of the svn-authz-file is: [/] * = r

The webrowser show me the login window, but on the server error log
appears this:

verification of user id '<null>' not configured

I try using the AuthType Basic with a htpasswd file and all works
perfectly, but with the Digest no....

What's the problem?

Thx ;)