node_comment_nodeapi($node, 'load', ...) does not set $comment_data['comment_target_cid'] from DB

As a result of this, hook_form_alter() (as well as the internal nodecomment_form_alter()) can't detect if the node is a reply to another comment while altering $type.'_node_form', when an existing comment is being edited, not created. Here is a patch that fixes it.