network problem

Hi all,
I spent the weekend trying to solve this, but I just can't understand what is happening:

I installed proxmox-ve_3.0-0428106c-13.iso on a fresh HP N40L, to setup a simple host to 2 VMs.
The VMs are ok, they are fully functional, access to the internet, the all thing.
my problem is with the network from the host...
I can ping other computers on my lan, but I cannot access the internet.
The really strange thing, at least for me, is that I can't ping my router!?!?
how is it possible to reach other machines in the lan and not the router, to which the server is physically connected?

my /etc/network/interfaces file:

##################
auto lo
iface lo inet loopback


auto vmbr0
iface vmbr0 inet static
address 192.168.1.253
netmask 255.255.255.0
gateway 192.168.1.254
bridge_ports eth0
bridge_stp off
bridge_fd 0
##################


I need to install acpid and without internet connection it would be a PITA

I run out of ideas (I even tried a simple dhcp setup for eth0, same result), any help appreciated!

thanks