According to this: http://www.w3.org/TR/xslt#attribute-sets It is possible to specify an xsl:use-attribute-sets in an xsl:attribute-set element. However, if you do that in FOP, it states '"xsl:use-attribute-sets" attribute is not allowed on the xsl:attribute-set element!'. Am I misreading the standard?
FOP implements the XSL-FO spec not the XSLT spec. You probably confusing the XSLT processing stage with the FO processing stage. FOP takes as input a FO document that is a document conforming to XSL-FO and produces output in the designated format. Typically the FO document is produced by an XSLT transformation of an XML input document but this is outside of the FO processing. I would check if your stylesheet is working correctly with your XML input, that is producing a valid FO document when processed through your XSLT processor.
batch transition to closed remaining pre-FOP1.0 resolved bugs