How to get the custom payload from pyapns using phonegap push plugin?

we are using PYAPNS to send push notifications from an Django application to iOS devices running an phonegap application.

The server code looks like this:

def sendNotificationAPNS(title, message, targets, eventid):
    apns = APNs(use_sandbox=False, cert_file='/path/to/push_cert.pem', key_file='/path/to/push_cert.pem')

        # Send a notification
        for token_hex in targets:
            payload = Payload(alert=message, sound="default", badge=1, custom={'eventid':str(eventid)})
            apns.gateway_server.send_notification(token_hex, payload)
            print('Notification to APNS send!')

        return true

On the mobile application the code from Phonegap Push Plugin looks like this:

// handle APNS notifications for iOS
function onNotificationAPN(e) {
    if (e.alert) {
        console.log('APNS Notifiation recieved: ' +  e.alert);
        // showing an alert also requires the org.apache.cordova.dialogs plugin
        navigator.notification.alert(e.alert);
    }

    if (e.sound) {
        // playing a sound also requires the org.apache.cordova.media plugin
        var snd = new Media(e.sound);
        snd.play();
    }

    if (e.badge) {
        pushNotification.setApplicationIconBadgeNumber(successHandler, e.badge);
    }
    //eventid
    if(e.eventid) {
        console.log('APNS eventid: ' + e.eventid);
    }

    //custom
    if(e.custom) {
        console.log('APNS eventid: ' + e.custom.eventid);
    }
}

The problem is: I don't get anything for e.custom or e.eventid?! What do I have to change to access the custom payload?

Thanks!