Problem with setting up Kerberos server

[sam]

Dear all,

I don't know how many of you setup Kerberos in OpenBSD.
I followed the instruction in OpenBSD website to setup kerberos server, but
I encountered problem when executing the ext_srvtab command:

root at sec [11:49am] [/etc/kerberosIV]# ext_srvtab sec

Enter Kerberos master password:

Current Kerberos master key version is 1.

Master key entered.  BEWARE!
ext_srvtab: couldn't get local realm

The /etc/krb.conf file is shown as below:
root at sec [11:52am] [/etc/kerberosIV]# cat krb.conf
rock.com        sec.rock.com admin server

/etc/krb.realms file is shown as below:
root at sec [11:53am] [/etc/kerberosIV]# cat krb.realms
rock.com                ROCK.DOMAIN
.rock.com               ROCK.DOMAIN

Host name is:
root at sec [11:53am] [/etc/kerberosIV]# hostname
sec.rock.com

Thanks very much
Sam