RT: Cannot Encode::Guess; fallback to iso-8859-1 ( /opt/rt/lib/RT/I18N.pm:352)

I am already using sendmailpipe and I am having the exact same problem. I
have tried switching back and forth and every time I try sending an email to
one of my queues, I get the following errors messages:

in /var/log/messages:
RT: Cannot Encode::Guess; fallback to iso-8859-1
(/usr/local/lib/rt3/RT/I18N.pm:352)

in /var/log/mailog:
rt-host sm-mta[717]: h6SFNAu6000717: from=hidden-name@hiddendomain.com,
size=703, class=0, nrcpts=1,
msgid=1F8ED810575FD511915600508BB8B49503EA624E@mailserver, proto=ESMTP,
daemon=MTA, relay=mailserver [X.X.X.X]
Jul 28 11:23:11 rt-host sm-mta[718]: h6SFNAu6000717:
to="|/usr/local/bin/rt-mailgate --queue tickets --action correspond --url
http://rt-webserver.com", ctladdr=tickets@rt-maildomain.com (26/0),
delay=00:00:01, xdelay=00:00:01, mailer=prog, pri=30961, dsn=5.3.0,
stat=unknown mailer error 9
Jul 28 11:23:11 rt-host sm-mta[718]: h6SFNAu6000717: h6SFNBu6000718: DSN:
unknown mailer error 9
Jul 28 11:23:11 rt-host sm-mta[718]: h6SFNBu6000718: to=<
hidden-name@hiddendomain.com >, delay=00:00:00, xdelay=00:00:00,
mailer=smtp, pri=31985, relay=mailrelayhost. [X.X.X.X], dsn=2.0.0, stat=Sent
(Ok - Data received)

I also get returned mail error on my mailbox:

" ----- The following addresses had permanent fatal errors -----
"|/usr/local/bin/rt-mailgate --queue tickets --action correspond --url
http://rt-webserver.com"
(reason: 9)
(expanded from: tickets@rt-maildomain.com)

----- Transcript of session follows -----
RT server error.

The RT server which handled your email did not behave as expected. It
said:

554 5.3.0 unknown mailer error 9 "
I am using perl version 5.6.1.

Charles Okochu
Snr. Network Engineer
MLBAM
Office: (212) 485-3473
Cell: (646) 996-3272 / (917) 518-5941From: Jesse Vincent [mailto:jesse@bestpractical.com]
Sent: Friday, July 18, 2003 2:11 PM
To: Don van der Haghen
Cc: rt-users@lists.fsck.com
Subject: Re: [rt-users] RT: Cannot Encode::Guess; fallback to iso-8859-1
(/opt/rt/lib/RT/I18N.pm:352)

Why don’t you switch from “sendmail” to “sendmailpipe” for your mail
transport and tell us how it works?