table vertical spans and page breaks

Hi,

I have a long table in which certain columns contain a large vertical 
span (using morerows attribute).

When printing to pdf with fop, fop page breaks this large vertical cell 
at an arbitrary place.

I have been trying to control this using the 'keep-together' directive, 
but I see no effect.

What is the best way to make sure fop will only break a table at the end 
of cell that spans multiple rows?

Thanks,

Marcel
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