Microstation Connect Edition Oracle autocommit

Within our application we have massive access to our Oracle database version 10g by means of client version 12.1

The connection works fine but for some reason we cannot set the AUTOCOMMIT mode OFF.

The call to mdlDB_activeAutoCommitMode(FALSE) returns SUCCESS but a successive call to mdlDB_isAutoCommit() returns TRUE.

In fact, any change in the database is committed immediately and both mdlDB_processSQL("commit") and mdlDB_processSQL("rollback") return SUCCESS without doing anything.

The very same statements in Microstation V8i SERIES 10 with Oracle client 11.2 work correctly.

Any idea what I'm doing wrong?