Why and how can it be fixed?

The local lib documentation shows you the magic

  # Just print out useful shell commands
  $ perl -Mlocal::lib
  export PERL_MB_OPT='--install_base /home/username/perl5'
  export PERL_MM_OPT='INSTALL_BASE=/home/username/perl5'
  export PERL5LIB='/home/username/perl5/lib/perl5/i386-linux:/home/use
+rname/perl5/lib/perl5'
  export PATH="/home/username/perl5/bin:$PATH"
[download]

Try this direct approach instead. Also try running Build.PL... manually