Openfire – Callback on offline plugin

We are looking for a freelancer to modify the Openfire plugin “Callback on offline” plugin.
https://www.igniterealtime.org/projects/openfire/plugins/1.2.1/callbackOnOffline/changelog.html

1) When a message sends do not “steal” the message from the user’s offline pool. When the user comes back online, he should get all the messages that were sent while he was offline.
2) Send in parameters entire message XML and not only the body.
3) Your responsibility to make sure the plugin works properly without bugs.