There should be an option in the user control panel settings to allow the user to manage the OpenID he connected with his UserEcho account, e.g. remove or change OpenID.
You should also support the addition of mutiple OpenID's to an account. This allows the user to be protected from being locked out of his account if his default OpenID provider discontinues their service. There are many websites out there that allow connecting multiple OpenID's to a user account.
Customer support service by UserEcho