The score isn't the problem, the problem is that mails sent from local users get scanned and there dynamic IPs get scored.
The mails are handled as they would get sent from an mx on that dynamic IP even though they're sent from local, logged in smtp users.
example:
Code:
pts rule name description
---- ----------------------
--------------------------------------------------
0.0 RCVD_IN_SORBS_DUL RBL: SORBS: sent directly from dynamic IP
address
[88.67.217.237 listed in dnsbl.sorbs.net]
0.0 FSL_HELO_NON_FQDN_1 FSL_HELO_NON_FQDN_1
3.6 RCVD_IN_PBL RBL: Received via a relay in Spamhaus PBL
[88.67.217.237 listed in zen.spamhaus.org]
1.6 RCVD_IN_BRBL_LASTEXT RBL: RCVD_IN_BRBL_LASTEXT
[88.67.217.237 listed in
bb.barracudacentral.org]
0.4 RDNS_DYNAMIC Delivered to internal network by host with
dynamic-looking rDNS
0.0 HELO_NO_DOMAIN Relay reports its domain incorrectly
1.4 DOS_OUTLOOK_TO_MX Delivered direct to MX with Outlook headers
They get marked as Spam before beeing sent which is quite nonsense
