steve@steve-desktop:~/.cpan/build/XML-LibXML-1.70-XzsnvX$ perl -w Makefile.PL
Name "main::is_win32" used only once: possible typo at Makefile.PL line 263.
enable native perl UTF8
running xml2-config...
using fallback values for LIBS and INC
options:
  LIBS='-L/usr/local/lib -L/usr/lib -lxml2 -lm'
  INC='-I/usr/local/include -I/usr/include'
If this is wrong, Re-run as:
  $ /usr/bin/perl Makefile.PL LIBS='-L/path/to/lib' INC='-I/path/to/include'

looking for -lxml2... no
looking for -llibxml2... no
libxml2 not found
Try setting LIBS and INC values on the command line
Or get libxml2 from
  http://xmlsoft.org/
If you install via RPMs, make sure you also install the -devel
RPMs, as this is where the headers (.h files) are.

Also, you may try to run perl Makefile.PL with the DEBUG=1 parameter
to see the exact reason why the detection of libxml2 installation
failed or why Makefile.PL was not able to compile a test program.