ssh: connect to host mi_otra_maquina port 22: No route to host

[xugnip en gmail.com]

Hola,

mi problema:

maquina2$ ssh -T user1 en maquina1
ssh: connect to host maquina1 port 22: No route to host

maquina2$ tcptraceroute maquina1 22
...
26  * * *
27  * * *
28  * * *
29  * * *
30  * * *
Destination not reached

maquina2$ ssh -vT user1 en maquina1
OpenSSH_5.9p1 Debian-5ubuntu1.1, OpenSSL 1.0.1 14 Mar 2012
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to maquina1 [maquina1] port 22.
debug1: connect to address maquina1 port 22: No route to host
ssh: connect to host maquina1 port 22: No route to host

maquina2$ sudo /sbin/iptables -L -n
Chain INPUT (policy ACCEPT)
target     prot opt source               destination
ACCEPT     udp  --  0.0.0.0/0            0.0.0.0/0            udp dpt:53
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:53
ACCEPT     udp  --  0.0.0.0/0            0.0.0.0/0            udp dpt:67
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0            tcp dpt:67

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  0.0.0.0/0            192.168.122.0/24     state
RELATED,ESTABLISHED
ACCEPT     all  --  192.168.122.0/24     0.0.0.0/0
ACCEPT     all  --  0.0.0.0/0            0.0.0.0/0
REJECT     all  --  0.0.0.0/0            0.0.0.0/0
reject-with icmp-port-unreachable
REJECT     all  --  0.0.0.0/0            0.0.0.0/0
reject-with icmp-port-unreachable

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

maquina1$ sudo /sbin/iptables -L -n
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

Donde puede encontrarse el problema?

Ambas maquinas conectadas por wifi, ambas Ubuntu 12.04.

Saludos a todos.