Open-Xchange built a framework based on Liquibase (http://www.liquibase.org) to enable declarative migrations of the configuration database. The changes involve two additional bundles and one command-line project:

- liquibase.core (Liquibase library)
- com.openexchange.database.migration (migration framework)
- com.openexchange.database.migration.clt (CLT)

Those are part of the open-xchange-core package.

The overall behavior was changed in a way, that possible database schema changes are scheduled asynchronously during the server startup and run in the background. To prevent from database inconsistencies the server shutdown via the 'open-xchange' init script blocks until all migrations are finished.

Documentation for admins as well as for developers can be found under http://oxpedia.org/wiki/index.php?title=AppSuiteBMigration.