Gateway+proxy server

[hotey]

Help solve the following problem here:
There Proxmox 2.0 on the basis of Debian6.
It employs more than ten virtualmachines(Wndows), IP subnet of the internal (192.168.*.*). This server is based on Debian should work as a gateway for virtual machines. But in the end they (virt.machine) must connect each to its proxy-server (which are outside the local network). In addition, these proxy-servers have authorization.
I would sincerely appreciate any help!

 

[hotey]

In VMs I chose to setup the network adapter NAT mode. And my proxmox-server began working as a gateway and dhcp-server. True, I have not found where to change settings.
VMs received the following settings:
IP - 10.0.2.15
mask - 255.255.255.0
gw - 10.0.2.2
dhcp - 10.0.2.2
DNS - 10.0.2.3
It remains only to make each virtual machine to goin to the world by proxy (but without any additional software on a virtual machine).Each virtual machine must have a separate proxy server.
And Proxmox should work as a caching proxy server. Or something like that.