Therein lies the rub, I think. A trace used for auditing would need to be running as long as the server is running or you would have to deny access to the database while you examine the log.

Since I am not really familiar with server-side traces, can you output the results to a table like you can with the Profiler GUI? I would assume you can, but then you now have the performance hit of the inserts as G mentioned in one of his posts.