If HTTP_SLUG is set:

New item will use the slug as the item title AND will use Dase_Util::makeSerialNumber($slug) for the serial number. Note that duplicate serial numbers will throw an error

If HTTP_SLUG is NOT set:

A new serial number will be created AND that serial number will appear as title.

For posted items, id atom:author/atom:name is set, it will be used in item table as "created_by_eid" (probably should be dirified!). If it is not set, http authorized user will be used