LedgerSMB began as a fork of SQL-Ledger. It has, however, diverged rapidly and the future architecture has very little to do with its ancestry.
The project began when Chris Travers, dissatisfied with the handling of security bugs in SQL-Ledger, partnered with Christopher Murtagh to produce a fix for CVE-2006-4244. strained relations between SQL-Ledger supporters and the members of the nascent LedgerSMB project.
The forking of LedgerSMB is considered by some in the short-lived SQL-Ledger Open Source License, the licence that was used for SQL-Ledger 2.8.0.