Check that your hostname is well declared in /etc/hosts:
mgirond@pepa:~$ hostname
xxxx
mgirond@pepa:~$ cat /etc/hosts
127.0.0.1 localhost
127.0.0.1 xxxx
# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
