Apache main site keeps redirecting to virtualhost

I have a website with Apache webserver, which hosts some subdomains too.

The problem I face is that once I activate any virtualhost, the main site keeps redirecting to the (yet only) virtualhost I have.

If I deactivate the virtualhost, everything works fine at the main site, but without my needed subdomain.

I'm using apache 2.2.19-1 under ArchLinux.

I have mydomain.com as the main site with the following httpd.conf:

ServerRoot "/etc/httpd"
Listen 80

#LoadModule section... a lot of LoadModule I omit

User http
Group http

ServerAdmin [email protected]

ServerName mydomain.com:80

DocumentRoot "/srv/http"

<Directory />
    Options FollowSymLinks
    AllowOverride None
    Order deny,allow
    Deny from all
</Directory>

<Directory "/srv/http">
    Options FollowSymLinks
    AllowOverride None
    Order allow,deny
    Allow from all
</Directory>

<IfModule dir_module>
    DirectoryIndex index.html
</IfModule>

<FilesMatch "^\.ht">
    Order allow,deny
    Deny from all
    Satisfy All
</FilesMatch>

ErrorLog "/var/log/httpd/error_log"

LogLevel warn

<IfModule log_config_module>
    LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined
    LogFormat "%h %l %u %t \"%r\" %>s %b" common

    <IfModule logio_module>
      # You need to enable mod_logio.c to use %I and %O
      LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\" %I %O" combinedio
    </IfModule>
    CustomLog "/var/log/httpd/access_log" combined
</IfModule>

<IfModule alias_module>
    ScriptAlias /cgi-bin/ "/srv/http/cgi-bin/"
</IfModule>

<Directory "/srv/http/cgi-bin">
    AllowOverride None
    Options None
    Order allow,deny
    Allow from all
</Directory>

DefaultType text/plain

<IfModule mime_module>
    TypesConfig conf/mime.types
    AddType application/x-compress .Z
    AddType application/x-gzip .gz .tgz
</IfModule>

# Some included conf files follow, I won't post them, just vhosts, but if needed ask me and I'll post them. As far as I know they aren't relevant
# Multi-language error messages
Include conf/extra/httpd-multilang-errordoc.conf
# Fancy directory listings
Include conf/extra/httpd-autoindex.conf
# Language settings
Include conf/extra/httpd-languages.conf
# User home directories
Include conf/extra/httpd-userdir.conf
# Virtual hosts
Include conf/extra/httpd-vhosts.conf
# Various default settings
Include conf/extra/httpd-default.conf

# Secure (SSL/TLS) connections
Include conf/extra/httpd-ssl.conf
<IfModule ssl_module>
  SSLRandomSeed startup builtin
  SSLRandomSeed connect builtin
</IfModule>

Here's my conf/extra/httpd-vhosts.conf:

NameVirtualHost *:80
Include conf/extra/vhosts/

And finally my conf/extra/vhosts/yetonlyvhost.conf

<VirtualHost *:80>
     ServerAdmin [email protected]
     ServerName subdomain.mydomain.com
     ServerAlias subdomain.mydomain.com
     DocumentRoot "/home/myuser/subdomaindir"
     DirectoryIndex indice.html
     ErrorLog "/var/log/httpd/vhost-error_log"
     CustomLog "/var/log/httpd/vhost-access_log" combined

    <Directory "/home/myuser/subdomaindir">
        AllowOverride None
        Order allow,deny
        Allow from all
    </Directory>
</VirtualHost>

(subdomain index must be file named 'indice.html')

Any ideas of what am I doing wrong? I had some similar configuration before on other server I lost, but I'm pretty sure almost is ok in here, but I haven't found what's wrong now...

Thank you!