Getting access to 10.4.11 mailboxes in 10.7 Mail

Question

Yesterday I migrated a user from a 10.4.11 machine to a 10.7 Lion machine.  When I launched mail, it only brought over the contents of her Inbox -- I had to put the accounts in again, and all of her mailboxes that she had stuff sorted into, and her Drafts, deleted messages, preferences, etc. did not get transferred over.
I can see the mail in her Library/Mail directory in the backup I made of her account before I started the migration.  Her saved mailboxes are in her Mail/Mailboxes directory with names like:
    Mail/Mailboxes/something.mbox/Messages/5-digit-#.emlx
while her old inbox, drafts, sent, etc are in a directory like:
    Mail/POP-user@hostname/something.mbox/Messages/5-digit-#.emlx
How can I get this mail loaded up into Lion (aka V2) mail?

Answer 1

To reply to my own question...  The trick here is that there was a mail upgrade between 10.5 and 10.6 and another one between 10.6 and 10.7.  My situation is a little different because I am working with Mobile accounts, but here's what I did...
Logged out of the user on the 10.7 machine and the 10.4 machine
Logged into a local Administrator account on the 10.4 machine
Used Terminal, with sudo su to be logged in as root.
used mv to get the Library/Mail/V2 directory out of Library/Mail
used used tar-through-a-pipe to get the contents of Library/Mail from my backup back in to the user's directory
used chown -R user:group on Library/Mail to fix the file ownerships
logged out of the Administrator account and logged into the user's mobile account on the 10.4 machine, this synch'd the file changes I made on the server.  Logged out of the 10.4 machine.
logged the user into a 10.6 laptop and synch'd the account on it, then launched mail.  This took the mail through the 10.5-to-10.6 upgrade. 
Then logged out of the 10.6 laptop, which synch'd the mail back to the server in that state
Then returned to the 10.7 machine and logged the user in, this time the synch brought over mail that had been upgraded to 10.6 and then launching mail got that upgraded to 10.7, with a new V2 directory created.
I took away a couple of morals to the story... 
If you want to use Mobile (home-synch'd) accounts simultaneously on computers with different operating systems, Mail is going to be your turd in the punchbowl.
If you are simply upgrading from one computer to another and never need to go backwards, there are two mail upgrades in getting from 10.4 to 10.7, so you will need a 10.6 machine to get the mailboxes updated out of 10.4 format to a format where 10.7 can update it.  (I know you can go directly from 10.4 mail to 10.6 mail, I just did it.  I know you can go from 10.6 mail to 10.8 mail, because we've done that before, too.  I presume we can get from 10.6 mail all the way to 10.9 mail, or all of those people running 10.6 who are having the "free" Mavericks update dangled in front of them are in for a pretty rude shock when it throws away years of accumulated email...)