[gracedman]

The reinjection seemed to work well. We put together a little script to facilitate it in case it helps anyone else:

#!/bin/bash
if [ $# -ne 1 ];then
        echo "Usage: $(basename $0) <Message store ID number>"
        exit 10
fi
if [ ! -d /opt/zimbra/store/0/${1}/msg/0 ];then
        echo "Could not find message store for ${1}"
        exit 11
fi

ZIMDIR="/opt/zimbra"
cd ${ZIMDIR}/store/0/${1}/msg/0/
for MSG in $(ls)
do
        TO=$(sed -n -e "1,/Original Message/ s/^To: \(.*\)/\1/p" ${MSG})
        FROM=$(sed -n -e "1,/Original Message/ s/^From: \(.*\)/\1/p" ${MSG})
        if [ -n "$(echo ${TO} | grep '<')" ];then
                TO=${TO##*<}
                TO=${TO%%>*}
        fi
        if [ -n "$(echo ${FROM} | grep '<')" ];then
                FROM=${FROM##*<}
                FROM=${FROM%%>*}
        fi
        ${ZIMDIR}/bin/zmlmtpinject -r ${TO} -s ${FROM} ${MSG}
done

We're still perplexed about why we had the problem in the first place. Any suggestions? Thanks - John