Network problems upon CT migration from proxmox 1.9 to 3.3

[raid]

I migrated a CT (ubuntu) from an OVH Proxmox 1.9 server to an OVH Proxmox 3.3 server using vzdump/vzrestore.

All goes fine but the migrated CT is not able to ping in outbounding.

Scenario as described in this post: :http://forum.proxmox.com/threads/19948-How-to-migrate-CT-from-Proxmox-1-9-to-3-3

Previous network model: use shorewall with NAT and Firewall.

New network model: proxmox default venet

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route and ifconfig on CT1

root@m1:~# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 venet0


root@m1:~# ifconfig
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:129 errors:0 dropped:0 overruns:0 frame:0
TX packets:129 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:24606 (24.0 KB) TX bytes:24606 (24.0 KB)
venet0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:127.0.0.2 P-t-P:127.0.0.2 Bcast:0.0.0.0 Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1
RX packets:563 errors:0 dropped:0 overruns:0 frame:0
TX packets:813 errors:0 dropped:2 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:59733 (58.3 KB) TX bytes:316976 (309.5 KB)
venet0:0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:192.168.2.101 P-t-P:192.168.2.101 Bcast:0.0.0.0 Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1
venet0:1 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:xxx.23.71.xxx P-t-P:xxx.23.71.xxx Bcast:0.0.0.0 Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1
venet0:2 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:xxx.196.149.xxx P-t-P:xxx.196.149.xxx Bcast:0.0.0.0 Mask:255.255.255.255
UP BROADCAST POINTOPOINT RUNNING NOARP MTU:1500 Metric:1


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looks like the proxmox panel GUI is not able to change CT setting

any tip?