Virtualbox XP on Feisty - Network question

I have ubuntu feisty with Virtualbox running an instance of XP Pro. I followed the instructions found in this forum to set up the host networking. It worked great for a few weeks and then I would lose my connection to my local network machine (not the internet) and have to reboot every 3 days or so. I posted a thread here about it but got no help.

I love this setup and it has allowed me to use ubuntu as my primary OS for the last 5 months. I have to have the XP running as I have to support clients with MS mail programs and other MS only items so totally abandoning it is not a choice.

I was thinking of adding a second network card to my ubuntu box and binding it to the vbox. Would this work? I would assign both cards seperate static IP addresses.

Please help me.

Thanks

Bob