Thread:Project:Support desk/Fatal error: Class 'XMLReader' not found in / local path to site /includes/Import.php on line 938

When attempting to import an xml file from another wiki, I get "Fatal error: Class 'XMLReader' not found in /usr/local/www/sites/wiki/includes/Import.php on line 938" This is FreeBSD 9.1, installing Mediawiki from the ports tree, along with all other needed software (php, etc). Anyone seen this before?