[Koha] koha requiring constant login/authentification

[Matthias & Melanie Kasimir <wahr at epost.de>]

Hi, 

I have the problem that koha 1.2.3 requires authentification (login) 
on each new page of the librarian's module. One mouseclick, one login 
- impossible to use  :-(

I tried it with mozilla 1.4 and with IE6. 

Koha is installed on debian 3.0 i386, perl v5.6.1,
Apache/1.3.26, mysql 4.0.13

Where should I look? What can I change to make koha require just one 
login per session?

Greetings from Germany, 

Mat