I’d just as soon keep the e1000 hack in place if I were a Xen admin. This is a severe artificial limitation in my opinion. I don’t suppose dd-wrt or pfsense (Zeroshell competitors) include Xen drivers?
Maybe buying a subscription from Fulvio might convince him to include Xen drivers in a kernel package, much like he did for Hyper-V that had a similar problem until recent releases (3.3.0?) included Hyper-V support. Then we could put together a Xen Tools hack similar to the VMware Tools hack to solve the rest of it.
[02 MAR 2015] Ask, and ye shall receive, apparently. Fulvio released a 64-bit kernel with Xen drivers today. Does this help?