I have a fairly simple sendmail setup with spamassassin (basically the Ubuntu out of the box setup) but I'd like to avoid running spamassassin checks for users who login to relay e-mails.

Basically, the reason is that when sending e-mails from my mobile phone my GPRS provider seems to be using an IP address listed in the spam black hole lists. The mail.log for such an e-mail looks like:

Apr 2 15:24:15 apollo sm-mta[3860]: AUTH=server, relay=[62.nnn.nnn.nnn], authid=barry, mech=LOGIN, bits=0
Apr 2 15:24:16 apollo sm-mta[3860]: n32DOCmY003860: milter_sys_read(verifymilter): cmd read returned 0, expecting 5
Apr 2 15:24:16 apollo sm-mta[3860]: n32DOCmY003860: Milter (verifymilter): to error state
Apr 2 15:24:17 apollo sm-mta[3860]: n32DOCmY003860: from=<barry@mydomain.xx>, size=355, class=0, nrcpts=1, msgid=<dLcbNRhj0cQQ.fhxTrzXd@mail.mydomain.xx>, proto=ESMTP, daemon=MTA-v4, relay=[62.nnn.nnn.nnn]
Apr 2 15:24:17 apollo spamd[2102]: spamd: connection from apollo.home [127.0.0.1] at port 45156
Apr 2 15:24:17 apollo spamd[2102]: spamd: setuid to spamass-milter succeeded
Apr 2 15:24:17 apollo spamd[2102]: spamd: processing message <dLcbNRdf0cPX.csdRrzXd@mail.mydomain.xx> for spamass-milter:122
Apr 2 15:24:18 apollo spamd[2102]: spamd: identified spam (9.2/5.0) for spamass-milter:122 in 0.2 seconds, 636 bytes.


Is there some way to tell sendmail not to run spamassassin for mails from authenticated users?