This problem occurs to a b2evolution 0.9x in a Linux box (Fedora core 4 and comparable MySQL, PHP version).
As a admin managing backoffice, I click on a category trying to edit its name. IE gives me error message 'page cannot be displayed....'. The URL for the error message page is http://host.domainname/......../admin/b2categories.php?action=Edit&cat_ID=16

I have another installation of b2evolution 0.9x in a local host in window XP box (Apache, MySQL, PHP). The same action as above just works fine.
The successful URL is http://localhost/admin/b2categories.php?action=Edit&cat_ID=11

What could go wrong with the Linux installation? And how to fix it?

Thanks for any help and hint.