"unknown" username being used instead of "<email address hidden>"

When a scanner forgets to login, the user log reports their name as "unknown"
When this happens, the desired action is for it to be uploaded with a generic username (which we agreed should be <email address hidden>)

However, the "unknown" username is still getting attached to the "operator" field in the meta xml

Please see:
http://www.us.archive.org/metamgr.php?f=histogram&group=operator&w_mediatype=texts&w_collection=microfilm*&w_scandate=20100731*&w_scanner=microfilm*p.sanfrancisco.archive.org&w_repub_state=!null

Note that you cannot click on the "unknown (batch)" link in the historgram....
Here is a direct link to one of these items: http://www.archive.org/details/populationsc18300011unit

The good news is that this problem does not seem to affect derivation.