Lost permalinks after multisite installation

Greetings,
I just activated and installed a path-based multisite. The installation went great, I can see the network dashboard and my previous site dashboard.

The issue is that I can not use permalinks with post-names anymore in the only site that i have (everything works fine without permalinks)

My .htaccess:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]
</IfModule>
# END WordPress

my http conf:

<VirtualHost *:80>
        ServerAdmin admin@mydomain.com
        ServerName mydomain.com
        ServerAlias www.mydomain.com

        DocumentRoot /srv/wordpress
        <Directory />
                #Options FollowSymLinks
                Options All
                AllowOverride All
        </Directory>
        <Directory /srv/wordpress/>
                #Options Indexes FollowSymLinks MultiViews
                Options All
                AllowOverride All
                Order allow,deny
                allow from all
        </Directory>

        ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
        <Directory "/usr/lib/cgi-bin">
                AllowOverride None
                Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
                Order allow,deny
                Allow from all
        </Directory>

        ErrorLog ${APACHE_LOG_DIR}/error.log

        # Possible values include: debug, info, notice, warn, error, crit,
        # alert, emerg.
        LogLevel warn

        CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

I followed http://codex.wordpress.org/Create_A_Network in every step, and as i stated before, i can access every page in the default format (page ids and without permalinks)

Thanks in advance