Upgrade from 3.22 to 4.0

[David B. Held]

I upgraded as stated in the subject, but my databases don't
show up in mysql.  The databases are still physically there,
but mysql just ignores them.  Apparently, it overwrote all
my old system db data, because the users and privileges
were gone too.  I installed the binary version first, hoping
that would be fast and painless.  It didn't work, so I installed
the source version, and it works fine, except that my system
information is gone.

I can add my databases back, but I can't re-create all the
tables, and I'm not sure what that would do.  The only step
in the upgrade guide I didn't do was the mysql_convert_
table_format script, because I didn't have DBD set up
on my perl installation, and had problems installing it.
Also, I wasn't sure if it was strictly necessary.

Is there a way to get my databases and tables back?  I
don't think I backed up my mysql db before upgrading
(which I obviously should have done, in retrospect).

Dave