I decided to take another shot at the OpenID Wordpress plugin, as Janrain / RPX 
(which I was using before) has other problems now.

Previously I had bug #130, but I'm now hitting different behaviour. Still 
doesn't work.

The server is running Mandriva Linux 2010.1 with packaged Apache, PHP etc. The 
plugin's self-test indicates that everything is OK (it can't check the version 
of curl because Suhosin is enabled, but it's easily new enough).

What happens is that if I go to the login page and try to log in using an 
OpenID - my Fedora project OpenID, http://adamwill.id.fedoraproject.org/ - it 
takes me out to the Fedora login system, as it should, I enter my Fedora login 
username and password, it asks if I want to allow happyassassin.net access to 
the OpenID info, I say yes, and it takes me right back to the login page, not 
logged in, with no error message. There are no errors I can find in the Apache 
logs, either.

Here's the only relevant lines in Apache's error_log:

[Wed Oct 27 14:56:11 2010] [error] [client 192.168.1.1] Successfully fetched 
'http://adamwill.id.fedoraproject.org/': GET response code 200, referer: 
http://www.happyassassin.net/wordpress/wp-login.php?loggedout=true
[Wed Oct 27 14:56:12 2010] [error] [client 192.168.1.1] Successfully fetched 
'https://admin.fedoraproject.org/accounts/openid/yadis/adamwill': GET response 
code 200, referer: 
http://www.happyassassin.net/wordpress/wp-login.php?loggedout=true

and here's the URL it sends me back to:

http://www.happyassassin.net/wordpress/wp-login.php?finish_openid=1&identity_url
=http%3A%2F%2Fadamwill.id.fedoraproject.org%2F&redirect_to=http://www.happyassas
sin.net/wordpress/wp-admin/&_wpnonce=7604c7xxxx

(I replaced the last four characters of that wpnonce thing with x's, in case 
it's some kind of sensitive identifier). It doesn't take me to the admin panel, 
as the redirect would indicate. It just goes back to the login screen, and I'm 
not logged in.

May be some kind of Apache configuration, but I'm not sure what. The Apache 
config file for Wordpress looks like this:

Alias /wordpress /var/www/wordpress

<Directory /var/www/wordpress>
    AllowOverride None
    Allow from All

#    Options FollowSymlinks
#    RewriteEngine On
#    RewriteBase /
#    RewriteCond %{REQUEST_FILENAME} !-f
#    RewriteCond %{REQUEST_FILENAME} !-d
#    RewriteRule . /index.php [L]

</Directory>

and there's also a .htaccess in /var/www/wordpress :

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress


Let me know if you need any other config details. Thanks.