Ask and FOP error

hello,

I've standard needs in a university, that are wiring books, articles, 
exercices, tech.
with text, figures and maths formulae
toward output on paper and web .

I actually use LaTeX for this and I'm looking at Docbook for a more 
model/content separation.

I load docbbok and standard tools : libxml, fop, jai, xerces to realise 
some exemples.
I have one question and one problem :

The question : are there some means to create and use maths formulae 
with docbook-xsl, same for graphics ?

the problem : a fop translation gives :
[INFO] Using org.apache.xerces.parsers.SAXParser as SAX2 Parser
[INFO] FOP 0.20.5
[INFO] Using org.apache.xerces.parsers.SAXParser as SAX2 Parser
file:///usr/share/docbook-xsl/fo/docbook.xsl; N° de ligne212; N° de 
colonne16; Making portrait pages on USletter paper (8.5inx11in)
[INFO] building formatting object tree
[INFO] setting up fonts
[ERROR] property - "background-position-horizontal" is not implemented yet.
[ERROR] property - "background-position-vertical" is not implemented yet.
what's up ?

Thank you very much for help.

Regards.

D.

-- 
Daniel Marre

Maître de Conférences
INSA - DGEI                   www.insa-tlse.fr
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