Default gateway unreachable from Guest OS

Hi!
    I have a W2K3 R2 SP2 server hosting a guest on Virtual Server 2005 R2 SP1. The guest machine is set to use the host network card to recieve the ip address. The host computer is connected to a segment which has a dhcp scope configured.
 Host ip = 10.13.152.10/22 default gateway = 10.13.152.1
Guest ip = 10.13.152.12/22
No the problem is that the guest OS is getting ip from the DHCP scope. I am able to ping the host computer, and from the host computer i am able to ping the guest. But i cannot reach the default gateway from the guest OS. I have tried to ping localhost address, guest ip, and host ip. All give a reply, but i cant seem to ping the router which is 10.13.152.1.
            I have had a similar problem with VMware, but no one was able to help me with a solution. The only solution was to install the host OS and try again. Well i have recently installed the Host OS and dont want to install it over and over again. Neither the host nor the guest have a firewall configured! Anyone had a similar problem before or have a suggesion for a solution? All help will be appritiated. Thanking you all in advance.