Making all in docs
make[1]: Entering directory '/home/alexandrogonsan/xfce4-dev-tools/docs'
xsltproc --nonet http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl xdt-csource.xml
I/O error : Attempt to load network entity http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl
warning: failed to load external entity "http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl"
cannot parse http://docbook.sourceforge.net/release/xsl/current/manpages/docbook.xsl
make[1]: *** [Makefile:533: xdt-csource.1] Error 4
make[1]: Leaving directory '/home/alexandrogonsan/xfce4-dev-tools/docs'
make: *** [Makefile:403: all-recursive] Error 1