Problem resolving names in VEs

All I got when trying to resolve a name inside any of my virtual machines was
ping: unknown host google.com

So I used tcpdump to debug the problem.

In the Hardware Node (HN) I executed:
# tcpdump -i venet0

And then tried to reach Google from a VE, getting this on the tcpdump output:

20:49:15.876485 IP 192.168.0.131.32943 > router.lan.domain: 36989+ A? google.com. (27)
20:49:16.207800 IP OpenVZ.lan > 192.168.0.131: ICMP host router.lan unreachable - admin prohibited, length 63
20:49:16.213804 IP 192.168.0.131.32943 > router.lan.domain: 36989+ A? google.com. (27)
20:49:16.215820 IP OpenVZ.lan > 192.168.0.131: ICMP host router.lan unreachable - admin prohibited, length 63


So it seemed to indicate that there was a problem with iptables.
Executing:
# iptables --list

I found that the cause of the problem was this last rule:
REJECT all -- anywhere anywhere reject-with icmp-host-prohibited

So I commented the corresponding line in /etc/sysconfig/iptables

#-A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited

I restarted iptables
# /etc/init.d/iptables restart

And now it works.

For further information on iptables look at:
Quick HOWTO : Ch14 : Linux Firewalls Using iptables