UserVoice OpenID Support
It is ironic that the OpenID foundation is using a service that does not support OpenID for new user registration. UserVoice used to support OpenID but has now removed it stating security concerns and email validation. You can read the concerns as posted by their staff here http://bit.ly/cnzvSW . Maybe you can contact UserVoice and help alleviate their concerns, and encourage them to re-implement support for OpenID, after all you are paying for their service.