API: 'create' - Phone creates duplicate records

Due to the deprecation of the 'update' function in the API, there doesn't appear to be a straightforward way of updating Phone records.

e.g if I do civicrm_api('Phone','create',$params) $params = array('version' => 3, 'contact_id' =>1, 'phone' ....) etc with the same phone_type_id it creates an additional, duplicate phone number.

This quirk isn't documented anywhere I can see. I assume I can use a get request to get the phone object with unique ID and update that way but its a bit inconvenient and should at least be documented somewhere. Do let me know if my understanding is wrong.