Thanks a lot.
Please keep in mind, that currently the workaround <property name="databaseSchemaUpdate" value="none" /> has to be used in order to assure, that the engine can start. This is a workaround and is not documented.
The situation occurs in cases where oracle is used, and you access the DB from the web application using e.g. APP_USER while the tables are created in the ADMIN_USER. This is usually done to implement security reducing the permissions for the APP_USER to the minimum.
<property name="databaseSchema" value="ADMIN_USER" />
<property name="databaseTablePrefix" value="ADMIN_USER." />
<property name="databaseSchemaUpdate" value="false" />
does not solve the issue, because the version check is performed during the engine startup (spring initialization) and the table with the version cannot be found.
This post can also be helpful http://forums.activiti.org/content/tables-missing-components-engine-history-identity