Checking if your kit is complete...
Looks good
Writing Makefile for Language::XSB::Config
Writing Makefile for Language::XSB::Base
Writing Makefile for Language::XSB::Register
Writing Makefile for Language::XSB::xsblib
Writing Makefile for Language::XSB
cp XSB.pm blib/lib/Language/XSB.pm
/Users/cpanrun/pristine/5.8.7/bin/perl "-I../blib/arch" "-I../blib/lib" Config.pm.PL Config.pm
inspecting XSB configuration...
****************************************************
unable to inspect XSB configuration. Be sure
that the 'xsb' program is in your command PATH.
****************************************************
make[1]: *** [Config.pm] Error 2
make: *** [subdirs] Error 2