are you using Oracle or Postgres? If oracle, 'tail -f' your server log as the server starts up and look for the error. If on postgres, make sure you installed only the fully-ported packages in the APM (see my post titled "Installation Tip" on the dotLRN->postgres port thread at https://openacs.org/bboard/q-and-a-fetch-msg.tcl?msg_id=00051T&topic_id=15&topic=dotLRN%20Development)
--dan