[Zope] Authentication problem / IE

[belen@netcom.no]

Hello ,

I have a problem regarding authentication and I do not know if 
authorisation. Users working IE5.01 SP2 cannot access my site. To enter 
it, I force them to login. When they do, their login and password is 
not rejected, but if I display their role/s and user name on screen it 
is
Role: ('Anonymous',)
Name: Anonymous User.

Some of the access of my site is granted by checking that their role is 
not Anonymous, (tried also their user name is not 'Anonymous User'), 
therefore they cannot access.

Surprisingly one of these users has Manager role. He still cannot 
access those parts of the site...but he can access the management 
screens of the site and access its content objects. Somehow zope 
still "knows" that he is not anonymous. This problem does not occur 
with IE 5.5 and IE 4.0. Has anyone have a clue of what happens. Could 
someone please point me to the solution?

Thanks in advance for your help.

Belen