When I delete a device, 2 fields stay filled in the DB

I'm using the fantastic Cool Solution "Datasync Web View".
This Cool Solution is a PHP webpage that pulls the data directly out of the postgresql database that datasync uses.

My question :

When I delete a device, the result in the database for the user is :
identifierstring : ' ' :)
description : Apple-iPad2C2/1001.523 :confused:
devicetype : ipad :confused:

In the Novell Data Synchronizer Web Admin, the device appear : Never Connected (Uninitialized)

In the database, the fields description and devicetype are always filled.

Is it correct ?
When will be this 2 fields empty ?

Thx

olidub