This means that you have to delete the db.ippool and db.ipindex files, because they think you are using the "old"(before changing) Ip-Range. Just delete them and touch them again.(dont forget to give the right permissions)
If you want to specify static adresses, do it in the Users-file directly. The entries in the users file would be Framed-IP-Address = 192.168.92.65, Framed-IP-Netmask = 255.255.255.255, greez Jan - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html
