trubles adding node on proxmox 2.1 cluster

[Ugo Vasi]

hi all,
I have a two nodes cluster (proxmox version 2.1-1/f9b0f63a) that is working fine since .
Now I've made a fresh installation of proxmox in a new server (same version) and I need to add it as a node of cluster.
I tried to add with the following console commands but without success:

root@proxmox01 ~ # pvecm addnode proxmox03 -votes 1
root@proxmox01 ~ # pvecm nodes
Node Sts Inc Joined Name
1 M 5428 2012-11-05 04:13:33 proxmox01
2 M 5432 2012-11-05 04:13:39 proxmox02
3 X 0 proxmox03
​

How can I find which is the problem?

thanks