Paket counters for aliased interfaces ?

[Patrick Mau]

Hello,

I would like to use IP-Aliasing to create a private network
between a few machines without buying more hardware. That's
easy, but ifconfig tells me:

eth0      Link encap:Ethernet  HWaddr xx:xx:xx:xx:xx:xx
          inet addr:x.x.x.x  Bcast:x.x.x.x  Mask:x.x.x.x
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:126810 errors:0 dropped:0 overruns:0 frame:1426
          TX packets:49286 errors:0 dropped:0 overruns:0 carrier:0
          collisions:15942 txqueuelen:100
          Interrupt:17

eth0:0    Link encap:Ethernet  HWaddr xx:xx:xx:xx:xx:xx
          inet addr:10.1.1.1  Bcast:10.1.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          Interrupt:17

And here's the question:
I would like to collect statistics for eth0:0 but obviously the
pakets are only counted for the real interface. If I had enough time
and knowledge, how should I implement paket counters for aliased
interfaces ?

PS: Am I right that it isn't possible ? tcpdump doesn't 'work right'
    either.