Mark RPM as Automatically or Manually Installed

A question exists regarding how to mark an RPM as automatically installed , but that question concerns Fedora. I am using zypper on OpenSUSE as an end-user and would like to know how to mark a package so that it will (or will not) show in the list of unneeded packages, with zypper packages --unneeded. I am looking for something along the lines of zypper mark autoselected [packageName]. A Novell Bugzilla bug mentions a status of byUser, and possibly autoselected, so it sounds like this information exists somewhere. I would like to know how to modify it.