Is there any reason you couldn't contact the Apache group and see what the story is? I would either patch the ErrorLog behavior to match what I required, or see if someone has done / will do the same thing.

Thinking right off the top of my head, I would envisage some key that is generated on each request. So if a 200 came in for page blah, and that generated a 500 error, both those messages would contain the same key, because conceptually they belong to the same HTTP 'session' for that particular page.

Just thinking out loud ...

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