help pls? imtest OK for localhost, fails for same box @ IP .... where to start looking?

[OpenMacNews]

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hi all,

testing my cyrus imap v 2.2.12 + sasl v 2.1.22, with:

	% imtest -t "" -p imap -m plain -a my.admin -u testuser at testdomain.com 127.0.0.1

i CAN login successfully

log: -->
	Oct  6 22:24:24 devbox DMCYRUS/imaplocal[2012]: login: localhost [127.0.0.1] blakers PLAIN+TLS
User logged in

BUT, if i change "localhost"-->"mail.testdomain.com", which is the SAME BOX, just the external
IP, login fails:

	imtest -t "" -p imap -m plain -a my.admin -u testuser at testdomain.com mail.testdomain.com

log: -->
	Oct  6 22:24:10 devbox DMCYRUS/imap[2010]: badlogin: mail.testdomain.com [10.0.0.6] PLAIN
[SASL(-13): user not found: Password verification failed]



i'm going nuts trying to track down the problem ... from my understanding, these two should
return the same result for the same box :-/

i'm GUESSING there's a config problem in imapd.conf, but for the life of me i dunno.

suggestions as to where to look?

thx!

richard
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