A SEVERE error like the following appears during the PDF generation of most of the manuals:
[fop] May 8, 2007 9:48:40 AM org.apache.fop.fo.PropertyList convertAttributeToProperty
[fop] SEVERE: Ignoring property: column-number="" (file:///C:/javadb/trunk/out/adminguide/derbyadmin.fo:523:788: No conversion defined ; property:'column-number')
It appears the following number of times for each manual.
The messages appear to have something to do with the processing of tables, but the number of messages has nothing to do with the number of actual tables in the manual, or with the number of colname, colnum, colwidth or other attributes, as far as I can tell.
The errors don't seem to affect the correctness of the generated output. For the Reference Manual in particular, however, they are a major nuisance. It would be desirable to know how to get rid of them, either by correcting the DITA source or by fixing the toolkit in some way.