WordPress behind reverse proxy: Session-cookies not set in Safari & IE

I have a WordPress blog running behind a reverse proxy (Apache). httpd.vhosts.conf: ``` <VirtualHost *:80> ServerName blog.domain.com:80 ServerAlias www.blog.domain.com ProxyPass / http://192.168.101.11/blog/ ProxyPassReverse / http://192.168.101.11/blog/ </VirtualHost> ``` The blog works fine, I can log in as admin, but when try to save settings or delete a plugin (and a wp_redirect occurs) I am redirected to the login page, because wordpress obviously doesn't find/accept the session cookie, and the action doesn't get completed. Therefore, I have added this line: ``` ProxyPassReverseCookiePath / http://192.168.101.11/blog/ ``` (see Apache proxy cookies works only with the first app) This seemed to solve the problem. However, I have noticed now, that with this setting, the login does not work at all, but only in Safari and IE (works just fine in Opera, Firefox, Chrome). I just get redirected to the login page again. Some additional information: - The session cookies and `wordpress_test_cookie` for the admin section are not created at all in Safari, only the ones like `"__uc*"` etc. (for the blog itself). Without the `ProxyPassReverseCookiePath`-entry, they are created. - I activated cookies for third-party-sites (in both browsers), this didn't solve the problem. - I've configured WP-cookies this way: wp-config.php ``` define('COOKIE_DOMAIN', '.blog.domain.com'); define('COOKIEPATH', '/'); define('SITECOOKIEPATH', '/'); define('ADMIN_COOKIE_PATH', SITECOOKIEPATH . 'wp-admin' ); ```