vboxnet0 doesn't count traffic correctly (Linux host)

[a_i_]

On a Linux box with VirtualBox 4.0.10 installed and with a Windows XP virtual machine with default settings.

ifconfig vboxnet0 does not show the reality :

[root@fedora15 ~]# ifconfig vboxnet0
vboxnet0  Link encap:Ethernet  HWaddr 0A:00:27:00:00:00
          inet adr:192.168.56.1  Bcast:192.168.56.255  Masque:255.255.255.0
          adr inet6: fe80::800:27ff:fe00:0/64 Scope:Lien
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1193 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 lg file transmission:1000
          RX bytes:0 (0.0 b)  TX bytes:274935 (268.4 KiB)

I've transferred much more than 268.4 KiB and obviously received some data.

Problem can also be seen with "tcpdump" which shows traffic only in one direction and "bwm-ng" which doesn't show any traffic at all.

This ticket is related to this post ​http://forums.virtualbox.org/viewtopic.php?f=7&t=38499 and to a conversation I've had on IRC where I've been told to fill in a bug report.

The Linux host is a Fedora 15 up to date (07/07/2011). Windows VM is also up to date.