Re : using sites or not - advice needed

Add the additional fields(better under Common Additional-Fields) as mentioned in the below link:
http://www.manageengine.com/products/service-desk/help/adminguide/configurations/user-management/configuring-user-defined-fields.html

and map it to the AD field like mentioned on the below link:
http://www.manageengine.com/products/service-desk/help/adminguide/configurations/user-management/configuring-active-directory-authentication.html

Maljeev
SDP Support - FAQ
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