In some cases the plugin may have problems if not enough memory has been allocated to PHP. Try ensuring that the PHP memory_limit is at least 8MB (limits of 64MB are not uncommon).
SSL certificate problems creep up when working with some OpenID providers (namely MyOpenID). This is typically due to an outdated CA cert bundle being used by libcurl. An explanation of the problem and a couple of solutions can be found here.
There are actually a couple of reasons that can cause this, but it seems one of the more common causes is a conflict with certain mod_security rules. See this blog post for instructions on how to resolve this issue.
First, be aware that this only works in WordPress 2.6 and up. Make sure you've
turned on SSL in WordPress by defining either of the following
globals as "true" in your wp-config.php file:
Then, also define the following global as "true" in your wp-config.php file:
Be aware that you will almost certainly have trouble with this if you are not using a certificate purchased from a well-known certificate authority.
Please direct support questions to the "Plugins and Hacks" section of the WordPress.org Support Forum. Just make sure and include the tag 'openid' so that I'll see your post. Additionally, you can file a bug report at http://code.google.com/p/diso/issues/list.




