The 1.95.5 release of expat fixes many bugs present in 1.95.4. One such bug is in entity handling and prevents the popular Perl module XML::Twig from installing. How to reproduce: get the latest XML::Twig tarball from CPAN, do perl Makefile.PL and make test. Two of the tests will fail. They do not fail with versions earlier than 1.95.4 of libexpat, and they do not fail with the latest version 1.95.5. This is known to be a bug in expat 1.95.4. (advocacy follows, skip if necessary) I don't know whether you consider it worth the effort to produce an erratum package for expat but since 1.95.5 is a pure bugfix release it seems reasonable. The maintainer of expat says: 'This release of Expat fixes a number of bugs, mostly minor, but annoying when you hit them. Some caused memory access violations, so if you've been using 1.95.4, it's probably worth updating.'
Fixed in expat-1.95.5-1.