Site to Site VPN Predicament...

I'm trying to set up a site to site VPN between 4 seperate sites. My problem is that at the main site they have 4 bonded routers. Where I would usually just put a Draytek in and do the VPN between the routers. Here I would rather set up the VPN on the server if possible to avoid touching the 4 bonded routers..

Is there anyway I can create the site to site VPN on the actual server? (SBS 2008) and then point the 3 other sites Draytek routers to it?

Thanks.