This question is becoming an FAQ. FOP is being redesigned to allow a good implementation of all the missing functionality for XSL:FO. We can't tell when full keep-with functionality is going to be available.
I have my old FOP FAQ here http://www.owal.co.uk/cgi-bin/fopfaq.cgi but it looked like someone else was producing a new one. Should I keep updating my old FAQ?
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