# Perl Readonly semantics changed with version 1.04. Readonly variable are
# readonly across contexts and thus unregistration of namespaces fails if
# the namespace variable is readoonly as the unregistration attempts to
# modify the value
diff -ru biblatex-biber-1.7.org/lib/Biber/Input/file/biblatexml.pm biblatex-biber-1.7/lib/Biber/Input/file/biblatexml.pm
---
 lib/Biber/Input/file/biblatexml.pm |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- lib/Biber/Input/file/biblatexml.pm
+++ lib/Biber/Input/file/biblatexml.pm	2014-01-31 19:25:36.000000000 +0000
@@ -23,7 +23,6 @@ use Log::Log4perl qw(:no_extra_logdie_me
 use List::AllUtils qw( uniq );
 use XML::LibXML;
 use XML::LibXML::Simple;
-use Readonly;
 use Data::Dump qw(dump);
 use Unicode::Normalize;
 use Unicode::GCString;
@@ -32,8 +31,8 @@ use URI;
 my $logger = Log::Log4perl::get_logger('main');
 my $orig_key_order = {};
 
-Readonly::Scalar our $BIBLATEXML_NAMESPACE_URI => 'http://biblatex-biber.sourceforge.net/biblatexml';
-Readonly::Scalar our $NS => 'bltx';
+our $BIBLATEXML_NAMESPACE_URI = 'http://biblatex-biber.sourceforge.net/biblatexml';
+our $NS = 'bltx';
 
 # Determine handlers from data model
 my $dm = Biber::Config->get_dm;