// HHVM: Class undefined: foo
// PHP5: Class 'foo' not found
if ( preg_match( "/Class (undefined: \w+|'\w+' not found)/", $msg ) ) {
// HHVM: Class undefined: foo
// PHP5: Class 'foo' not found
if ( preg_match( "/Class (undefined: \w+|'\w+' not found)/", $msg ) ) {