3 calls to user_external_load()

openid_authentication in modules/openid/openid.module
Authenticate a user or attempt registration.
user_external_login_register in modules/user/user.module
Helper function for authentication modules. Either logs in or registers the current user, based on username. Either way, the global $user object is populated and login tasks are performed.
_openid_invalid_openid_transition in modules/openid/openid.inc
Provides transition for accounts with possibly invalid OpenID identifiers in authmap.

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