I just installed 4.0 EA1 and imported the settings from 3.1. When I try to connect to my local DB (11gR2 on Win7) I get
ORA-00904: "DBMS_TRANSACTION"."LOCAL_TRANSACTION_ID": invalid identifier.
When I go to the connection properties and choose "test" for the connection it shows "success".
The error does not occur when I don't import the settings of another version on first startup.
Edit: Seems like the db does not run correctly since a restart after installation of the latest MS security update.