Possible to use Vaadin as a proxy?

In my Vaadin application, I want to server content from other HTTP servers. This can usually be done by using the BrowserFrame introduced in Vaadin 7. The component however does only create an iframe on the client side and forces it to access the resources on the other server directly.

I have the situation, that the other server might not be accessible from the client, as the vaadin application is running in a DMZ, the other web server in the intranet and the client is from outside the network.

This leads to the client not beeing able to load the additional resources. How can i use Vaadin to proxy the request from the client and make it therefore accessible?

After further testing it came to me that the only solution might by a full-bodied http proxy where the only additional work you do is to map host and port of the incoming requests. Does anyone have any experience with embedding such a feature in Vaadin?