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[Otto Stolz]

PS.

I have written:
>   To avoid unneccessary LDAP requests, these functions store the
>   server, and user, information in the session data, and update it
>   only on the 1st invocation of any one of them

Note that I have disabled "alternate identities". If I would allow
these, I would have to keep in the session data the particulars for
each identity and, of course, ask the LDAP server when a particular
identity is accessed for the 1st time during a session. I have not
really looked in the implications of enabling alternate identities,
though.

Cheers,
   OS