Apache 2.0 + virtual host + mod alias

Hi,

I'm trying to serve up one file that would not be in its virtual
host's DocumentRoot
My configuration looks like that:
<VirtualHost 12.34.56.78:17191>
ServerName mysite.com
ServerAlias www.mysite.com
Alias /sitemap.xml.gz /someotherdir/sitemap.xml.gz
DocumentRoot "/usr/local/tomcat/webapps/mysite/"
CustomLog "/var/log/httpd/access_mysite_log" "%{PC-Remote_Addr}i
%l %u %t \"%r\" %>s %b"
LogLevel debug
ErrorLog "/var/log/httpd/error_mysite_log"
JKMount /* Tomcat
Options -Indexes
RewriteEngine On
RewriteCond %{HTTP_HOST} ^mysite.com
RewriteRule (.*) http://www.mysite.com$1 [R=301,L]
</VirtualHost>

The line
Alias /sitemap.xml.gz /someotherdir/sitemap.xml.gz
doesn't seem to do anything. Nothing in the logs except that it
returns a 404 when requesting www.mysite.com/sitemap.xml.gz:
- - - [08/Jul/2007:15:23:46 -0400] "GET /sitemap.xml.gz HTTP/1.1" 404
985

Can I map a single file using mod alias? (it's not clear whether it's
feasible from the doc)
If not, what should I do?


Luc.