Database migration tool does not work

Nap reported the problem on the user list:
http://www.nabble.com/DB-Migration-Tool-in-Continuum-1.2.3-not-working-td21483002.html

Has anyone tried the db migration tool in continuum 1.2.3 using the instructions in
http://continuum.apache.org/docs/1.2.3/installation/upgrade.html? I tried
the same procedure in a 1.2.3 database to import to a 1.3.0 (not yet
released) database, but I'm having the following error:

$ java -Xmx512m -jar data-management-cli-1.2.3-app.jar -buildsJdbcUrl
jdbc:derby:/tmp/apache-continuum-1.2.3/data/databases/continuum -mode EXPORT
-directory backups
Exception in thread "main" java.lang.NoClassDefFoundError:
org/apache/continuum/management/DataManagementCli