capture port-mirrored(SPAN) traffic on a VM where interface is bridged with tap interface on host

First of all, sorry about bit clunky title. Tried to make it as informational as possible.

I have a following topology in GNS3:

"SW" is a Cisco 3640 router with NM-16ESW 16-port 10/100 EtherSwitch Network Module. Port Fa0/0 of "SW" is an access port in VLAN 5. I have mirrored both Rx and Tx traffic of port Fa0/0 to port Fa0/10:

SW#sh run | i monit
monitor session 1 source interface Fa0/0
monitor session 1 destination interface Fa0/10
SW#sh monitor session 1
Session 1
---------
Source Ports:
    RX Only:       None
    TX Only:       None
    Both:          Fa0/0
Source VLANs:
    RX Only:       None
    TX Only:       None
    Both:          None
Destination Ports: Fa0/10
Filter VLANs:      None
SW#

There is a Debian VM running Wireshark 1.2.11 listening on eth2 interface which is bridged with tap0 interface in Virtualbox configuration. VM eth2 interface is connected to port Fa0/10. Now if I telnet to “router” from “R1”:

R1#ping 10.10.10.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/7/16 ms
R1#telnet 10.10.10.2
Trying 10.10.10.2 … Open
router>exit
[Connection to 10.10.10.2 closed by foreign host]
R1#

..I expect to see ARP, ICMP and IP traffic in Wireshark output. However, I capture only SPT and CDP traffic:

Any ideas what might cause this?