What ADK are you using? And are you on NT or UNIX?
I have had similar problems, and as a result I have had to create a cron job that restarted the oracle adapters at 6:00 am to make sure everything was working at the beginning of the day. I also made sure that I stop and restarted the adapters in sync with when the database goes off line for backups.
This has helped make sure that I am not hunted down by users saying that things are not working, when I get into the office.
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