jade errors (how to convert balsa.sgml?)

[Toralf Lund <toralf kscanners com>]

Following an upgrade to Red Hat 7.3 + some messing around with sgml/xml 
and docbook packages I get a large number of error messages from jade when 
building balsa. The first few lines of the output are:

Using catalogs: /etc/sgml/catalog, /etc/sgml/catalog
Using stylesheet: 
/usr/share/sgml/docbook/utils-0.6.9/docbook-utils.dsl#html
Working on: /u2/work/GNOME/balsa/help/C/balsa.sgml
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:1:70:W: cannot generate system 
identifier for public text "-//GNOME//DTD DocBook PNG Variant V1.1//EN"
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:20:0:E: reference to entity 
"ARTICLE" for which no system identifier could be generated
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:1:0: entity was defined here
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:20:0:E: DTD did not contain 
element declaration for document type name
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:52:12:E: there is no attribute 
"ID"
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:52:19:E: element "ARTICLE" 
undefined
jade:/u2/work/GNOME/balsa/help/C/balsa.sgml:54:10:E: element "ARTHEADER" 
undefined

I suspect that I have accidentally disabled PNG variant of DTD. What do I 
need to re-enable it? Also, what is necessary in general to properly build 
doc from balsa.sgml?

/etc/sgml/catalog is

CATALOG "/etc/sgml/sgml-docbook-3.0-1.0-8.cat"
CATALOG "/etc/sgml/xml-docbook-4.1.2-1.0-8.cat"
CATALOG "/etc/sgml/sgml-docbook-3.1-1.0-8.cat"
CATALOG "/etc/sgml/sgml-docbook-4.0-1.0-8.cat"
CATALOG "/etc/sgml/sgml-docbook-4.1-1.0-8.cat"

-- 
Toralf