<p>I am using sfOpenID plugin for Symfony, which doesn't support OpenID 2.0. That means, for example, that people using Yahoo! OpenID can't login to my site.</p>

<p>There is an OpenID 2.0 plugin that works with sfGuard, but I am not using nor planning to use sfGuard. Plus, it requires to install Zend framework, too, which is an overkill in my scenario.</p>

<p>So I've got two questions, really:</p>

<ul>
<li>is there another OpenID plugin for Symfony supporting OpenID 2.0?</li>
<li>what would be the hack required to make sfOpenID support OpenID 2.0?</li>
</ul>

<p>I suppose I could study OpenID specs and hack it myself, but then, I am a lazy programmer :)</p>

I think you've covered all your options with sfOpenID and taOpenIDsfGuardPlugin for Symfony's plugins.
Without studying OpenID's specs in detail though, you could try one of those PHP libraries (
http://wiki.openid.net/Libraries
) by dropping it in your lib and connecting to a
```
sfUser
```
, or whatever you're using for authentication. There is also the OpenID Enabled library (
http://openidenabled.com/php-openid/
) which still uses PHP4 although compatible with PHP5 if you
tweak the error reporting level
to exclude some warnings.
There are a few tutorials out there that explains how to enable OpenID on your site with PHP:
http://www.saeven.net/openid.htm
or
http://www.plaxo.com/api/openid_recipe
.
And better yet, use this knowledge to
make a sfPlugin out of it
afterwards.