Assuming you mean the database tables are generated via hbm2ddl.auto being set to CREATE or similar, there is no way to specify the order of the columns at least in 2008, according to one member of the Hibernate team.
My advice would be to create the database via separately maintained database scripts (possibly in conjunction with a script deployment/migration tool such as Flyway and perhaps also with hbm2ddl.auto = VALIDATE to check the resulting schema matches the entities). Maintaining the database via scripts becomes much more necessary once the application goes into production.
