Rt-mailgate issue

I have rt3 up and running, but users are unable to reply to emails.
Outbound mail is working fine.

Sendmail reports the emails having the following error:

Oct 21 17:36:59 rt sendmail[3081]: h9LLawow003080:
to="|/opt/rt3/bin/rt-mailgate --queue general --action correspond

–url http://rt.nubridges.com/", ctladdr=rt@rt.nubridges.com (8/0),
delay=00:00:01, xdelay=00:00:01, mailer=prog,

pri=31007, dsn=5.3.0, stat=unknown mailer error 255

Software Versions:

RedHat 9.0

mysql Ver 11.18 Distrib 3.23.56

Perl, v5.8.0


Some things I have tried to fix the issue:

verfiy the link from /etc/smrsh/rt-mailgate to /opt/rt3/bin/rt-mailgate

I am able to send a mail to root@rt.nubridges.com.

I have verified that the version of MIME::Tools I am running is 5.411

I have used lsof to verfiy that rt-mailgate is being called by sendmail,
and it is.