ASA 5510 and Cisco 2811 router dot1Q?

My question is this: Our ISP has assigned us with a single network segment of x.x.28.x/29. We then needed more public IP’s so we requested another /29 octet. They then assigned us x.x.27.x/29. Our current setup is the MPLS Internet connection demark, to a Cisco 2811 Router that has a WAN ip of a /30 and an inside ip of the /29. Then from that it goes to a Cisco ASA 5510 with the outside ip another public /29, and the inside is a 172 addressing scheme. My question is, with the new network set they gave us, can I configure dot1q in between the router and the ASA to get both networks over that link then configure the translation on the ASA? If so, how? Any help is appreciated! THANKS A MIL!! Kris