System cannot find user IDs

Please CC me on any replies.  I'm on my wife's machine writing this and 
I can't get to my mornal MUA.

I've been working on setting up MySQL and I have been having problems 
with the MySQL root user.  Thinking I might have changed the user to 
upper case when I changed it from root (based on a best practices 
article from onlamp.com) I added the MySQL admin id in upper case.

I got a message that the user id had disappeared during the add.  (I've 
never seen this message before.)  I'm assuming it came out of the 
adduser command.

I tried to remove the ID and I started getting messages from various 
places complaining about user IDs.  Thinking something might be out of 
sync, I rebooted.  (Appears to be a very bad idea in hind sight.)

It seems like every daemon complains at boot that it cannot find one 
user id or another.  I also cannot sign on to the machine.

I was able to get into the machine in single user mode.  I took a recent 
backup  I made of ad0s1a to another machine, untared it, copied passwd 
and master.passwd to a floppy and restored them to the failing machine. 
  The reboot after restoring passwd and master.passwd gave me the same 
results.  I can still get on the machine in single user mode.
The FreeBSD Handbook didn't help me much so I looked at Greg L's The 
Complete FreeBSD and he talks about some db files (/etc/pwd.db and 
/etc/spwd.db) on the bottom of page 163.

After reading that and some hits searching the questions list I decided 
it was time to ask for help.  I'm in way over my head this time!

I'm not sure how to dig myself out of this.  TIA.