I'm surprised to hear you say that it fails with gmake too, since that's what 
I use. What version of GNU make?

> Sorry, it's been too long since I did this.

You shouldn't need to apply the patch manually; if you take the attachment and 
pipe it into the patch program, it will make the change automatically, like 
so:

patch man/Makefile.am < /path/to/message/attachment

But if you want to apply the patch manually, read on.

> So, I read this as repalce the line:
>
>       $(XSLTPROC) --path xslt/ --output $@ man.xsl $<
>
> with
>
> %: xml-source/%.proc.xml $(srcdir)/xslt/man.xsl
>
> am I reading this corectly?

No, you should replace the line
$(man_MANS): %: xml-source/%.proc.xml $(srcdir)/xslt/man.xsl
with
%: xml-source/%.proc.xml $(srcdir)/xslt/man.xsl

that is, to remove the  $(man_MANS): at the beginning of the line.

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