[TYPO3-english] can't set permissions for content element based on user group

[Stefanos Karasavvidis]

What Access List option of a BE usergroup do I have to enable, in order
for a BE user to be able to set access for a content element based on FE
groups (general options->access of a content element)?

Whatever I do, the list of user groups is always empty, except the "Hide
at login" and "Show at any login"

any help?
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Stefanos Karasavvidis
Electronic & Computer Engineer, M.Sc.
e-mail : sk at isc.tuc.gr

Technical University of Crete, Campus
Information Systems Center
Address: Akrotiri, Chania, 73100
Tel.: Main Buildings - next to Library (G1),    (+30) 28210 37400
      Environmental Engineering Buildings (K2), (+30) 28210 37766
Fax:  (+30) 28210 37571