proxy.conf and virtual_server

[Marc Boisis-Delavaud <mdelavau@univ-lr.fr>]

Hello,

I have two virtual server which listen on the same IP.
According to realm in proxy.conf, I wich to proxy on virtual1 or  
virtual2.
Is it possible to write this in proxy.conf ?

realm toto {
	"proxy to virtual_server" = virtual1
}