Getting new comment alerts in node author´s email
To do this, we need to create a new action of type “send an email”, put %author on the author field and customize the subject and body of email to be sent; under site building>triggers>comment we need the “After saving a new comment” trigger – go to the drop down box in it and then select the Action made earlier. Click “Assign” and it´s done.
Do not forget to add under site information the email address for the “From:” field.
This was of help: http://drupal.org/node/199254
EDIT: %author causes the mail function to crash. It turns out that is sending an email to the author of the comment, not the author of the node. Use a hard coded email here then instead.