OpenID failure causes permanent setting of drupal_http_request_error = true

I'm encountering errors with my openid (another issue) which causes the 'drupal_http_request_error' variable to be written to the variables table. It does not ever seem to be cleared despite apache having external socket access. Deleting the variable or setting it to false will return the site to working order. i.e. It will be able to check for updates.

To summarise, an error in OpenID seems to permanently disable outbound socket access.