This may be a bit surprising to you, but it really isn't particularly "weird".
When you use disable-output-encoding, Xalan generates a processing instruction to pass this formatting hint to the serializers. Our serializers respond to that PI and discard it. If you view Xalan's output directly, though, you'll see it ... and you probably _want_ to see it, since that way if you run through our serializers after doing your own processing the disable-output-escaping will be honored. If you don't want it, don't specify disable-output-escaping, or plug in a filtering stage which discards these PIs; take your pick. But note that PIs should be ignored by any application that doesn't specifically recognize and process them (per the XML spec), so this should be harmless in any case. The output is _correct_; it's just carrying a bit of additional annotation.
