Hi Joseph,
I just finished the process of moving from SQL-Ledger 2.4.something to
a new machine with LedgerSMB 1.2.4 and had the same errors. It was a
Postgresql change that fixed it for me. I run Ubuntu 9.04 and
LedgerSMB simply would not run the database upgrades reliably with
Postgresql 8.3. I hammered my head against the virtual wall for 3 days
and then decided to try postgresql-8.2. If you too are running Ubuntu,
I can send the deb files via email.
If I recall correctly, you don't want to go above SQL-Ledger version
2.6 if you want to safely migrate to a 1.2 series LedgerSMB...