127:~/.cpan/build/Mozilla-DOM-0.21# perl Makefile.PL
Package mozilla-xpcom was not found in the pkg-config search path.
Perhaps you should add the directory containing `mozilla-xpcom.pc'
to the PKG_CONFIG_PATH environment variable
No package 'mozilla-xpcom' found
Package firefox-xpcom was not found in the pkg-config search path.
Perhaps you should add the directory containing `firefox-xpcom.pc'
to the PKG_CONFIG_PATH environment variable
No package 'firefox-xpcom' found
Package mozilla-firefox-xpcom was not found in the pkg-config search path.
Perhaps you should add the directory containing `mozilla-firefox-xpcom.pc'
to the PKG_CONFIG_PATH environment variable
No package 'mozilla-firefox-xpcom' found
*** can not find package for any of (mozilla-xpcom >= 1.7, firefox-xpcom >= 1.0, mozilla-firefox-xpcom >= 1.0)
*** check that one of them is properly installed and available in PKG_CONFIG_PATH
 at Makefile.PL line 43