Thanks for the reply.
I attempted to undo what I'd done to no avail. Shortly after that, I backed up the SME, reloaded it, and restored. This seemed to restore mail delivery, but left me a mess when I attempted to reload some of my contribs. Then the SME stopped delivering again this morning.
I've since reloaded again, used the LATK to create users, and am in the process of loading everything back up.
One problem - I've got an account I can't create. The LATK errored out when creating his account. When I re-ran the account portion, it said successful. After trying to reset his password, I realized the account was hosed.
/sbin/e-smith/db accounts delete username has no affect on the account, and there's no record of the account in /etc/passwd or /home/e-smith/accounts.
Most of the threads I'm finding about deleted users reference the above command, and every reply I've found claims it's fixed the problem. I'm on 6.01-01 custom.