Bugsnag missing events with £ symbol in custom data

test.js

// add your API key, & run with `npm install bugsnag@1.3.0 && NODE_ENV=development node test.js`
// only the second error appears in the dashboard

var bugsnag = require('bugsnag');

bugsnag.register('/* key */', {
  appVersion: 'N/A',
  notifyReleaseStages: [ 'development' ]
});

bugsnag.notify(new Error('Pound symbol in extraData bad path test'), {
  extraData: {
    currency: '£'
  }
});

bugsnag.notify(new Error('Pound symbol in extraData good path test'), {
  extraData: {
    currency: 'POUND'
  }
});