[Exim] Question concerning lookups

Hi,

I'm using the following ACL with Exim 4.14:

---8<---
   deny    hosts         = +reject_from_hosts
           message       = Keep your spam.
---8<---

The definition of the hostlist is a simple one:

hostlist reject_from_hosts = /etc/exim/blacklist_hosts

and /etc/exim/blacklist_hosts contains entries like:

192.168.254.105
[...]


Okay, everything works fine:

---8<---
26510 processing "deny"
26510 check hosts = +reject_from_hosts
26510 host in "/etc/exim/blacklist_hosts"? yes (matched
"192.168.254.105" in /etc/exim/blacklist_hosts)
26510 host in "+reject_from_hosts"? yes (matched "+reject_from_hosts")
26510 deny: condition test succeeded
26510 SMTP>> 550 Keep your spam.
---8<---

BUT ... let's change the ACL to the following:

---8<---
deny hosts = dbm;/etc/exim/dbm/blacklist_hosts.dbm
      message       = Keep your spam.
---8<---

The dbm file has been created with exim_dbmbuild. Okay, let's have
a look at Exim's output:

---8<-­--
26504 processing "deny"
26504 check hosts = dbm;/etc/exim/dbm/blacklist_hosts.dbm
26504 search_open: dbm "/etc/exim/dbm/blacklist_hosts.dbm"
26504 search_find: file="/etc/exim/dbm/blacklist_hosts.dbm"
26504 key="hal9000.intern.ilk.de" partial=-1 affix=NULL starflags=0
26504 LRU list:
26504 1/etc/exim/dbm/blacklist_hosts.dbm
26504 End
26504 internal_search_find: file="/etc/exim/dbm/blacklist_hosts.dbm"
26504 type=dbm key="hal9000.intern.ilk.de"
26504 file lookup required for hal9000.intern.ilk.de
26504 in /etc/exim/dbm/blacklist_hosts.dbm
26504 lookup failed
26504 host in "dbm;/etc/exim/dbm/blacklist_hosts.dbm"? no (end of list)
26504 deny: condition test failed
---8<---

Now Exim doesn't search for the hosts IP, it looks for it's FQDN. I've
noticed the same behaviour after leaving the ACL definition in it's
original state and using

hostlist reject_from_hosts = dbm;/etc/exim/dbm/blacklist_hosts.dbm

or

hostlist reject_from_hosts = lsearch;/etc/exim/blacklist_hosts

and I'm quite confused. Should I just take a rest and try to regain
the capability of clear thinking? Did I understand something wrong
when reading the docs concerning "hostlist", "domainlist" and dbm
lookups? Or is this indeed some kind of misbehaviour?

--
Ralf Ramge                                    E-Mail: ralf.ramge@???
ILK Internet GmbH                             Tel:       +49 721 9100 0
Akademiestrasse 25 - 27                       Fax:     +49 721 9100 191
D-76133 Karlsruhe                             WWW:    http://www.ilk.de