Scripting problem

[Paul Schmehl]

I'm writing a bash script to create a db backup and email it to me once a 
day. I'm munged some parts to not reveal details

I'm having a problem with this line:

/usr/local/bin/mutt -s $SUBJECT -i $MESSAGE -a $FILENAME -- 
pschmehl at tx.rr.com < /dev/null

Right before this line are these lines:
MESSAGE="path/to/message.txt"
ADDRESS="pschmehl at mydomain"
SUBJECT="Today's db backup"

>From the commandline this runs fine, but the script returns an error:

Error sending message, child exited 67 (User unknown.).
Could not send the message.

The mail is sent, and when it's received, the subject line is Today's. When 
I look in the maillog, mutt tried to send email to db at hostname and 
backup at hostname.

I changed the subject to Backup, and the error goes away.

I'm running FreeBSD 10.3-RELEASE and the script is written in bash.

Why would mutt do this?

Paul Schmehl, Retired
As if it wasn't already obvious, my opinions
are my own and not those of my employer.
*******************************************
"It is as useless to argue with those who have
renounced the use of reason as to administer
medication to the dead." Thomas Jefferson
"There are some ideas so wrong that only a very
intelligent person could believe in them." George Orwell