This sounds like a log4j problem or a dtd resolution
That's what you would think, but the DTD is available in the log4j jar, so it can be found.
It is more of a validation problem. I thought the parser did not validate correctly, so it was using the wrong parser, but after some debugging I found that log4j DOMConfigurator was really using crimson as a parser, so that probably is not the problem.
Any more specific idea's?
I replaced the standard log4j with a newer one : 1.2.8, but still the same problem...