Initial Interface cofiguration:

eth0      Link encap:Ethernet  HWaddr 00:16:3e:31:c4:a0 
          inet addr:217.70.188.124  Bcast:217.70.191.255  Mask:255.255.252.0
          inet6 addr: fe80::216:3eff:fe31:c4a0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1580 errors:0 dropped:0 overruns:0 frame:0
          TX packets:733 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:210383 (205.4 KiB)  TX bytes:117165 (114.4 KiB)

lo        Link encap:Local Loopback 
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

sit0      Link encap:IPv6-in-IPv4 
          NOARP  MTU:1480  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

mkv6 returns

Attempting to obtain current ipv4 address..
Using hostid to obtain address..
DBG:  46d97cbc
 ...
Got 217.70.188.124 ...
-- Adding 2001:4b98:41::d946:bc7c:124/64 to device eth0
-- setting IPv6 default gateway via FE80::641 on eth0

The configuration or eth0 changed into:

eth0      Link encap:Ethernet  HWaddr 00:16:3e:31:c4:a0 
          inet addr:217.70.188.124  Bcast:217.70.191.255  Mask:255.255.252.0
          inet6 addr: fe80::216:3eff:fe31:c4a0/64 Scope:Link
          inet6 addr: 2001:4b98:41::d946:bc7c:124/64 Scope:Global
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:58519 errors:0 dropped:0 overruns:0 frame:0
          TX packets:17470 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:71932470 (68.6 MiB)  TX bytes:3506976 (3.3 MiB)