[SunHELP] messages

[Vivas Inga, Yovana Mery]

Hi, every minute I receive these messages in the /var/adm/messages file:

Jun 30 04:15:07 atmb1 sendmail[22307]: My unqualified host name (atmb1)
unknown; sleeping for retry
Jun 30 04:15:29 atmb1 sendmail[21856]: unable to qualify my own domain name
(atmb1) -- using short name

the hostname of this sun station is atmb1.
why does the server get theses messages all the time? can I fix it?
thanks for your help
Mery