The problem is caused by the fact you have no MX record for your domain name, your domain name is actually this: hcjbc.dyndns.org What you are using above (BCmysql.hcjbc.dyndns.org ) is the Fully Qualified Domain Name of your server (FQDN) and is not correct. You should modify your DNS server to reflect that and use the correct domain name.
BTW, I'd recommend you change all your DNS records (and your hosts file) to have all the domain name and server FQDN in lower case, you may hit problems later on if you leave it as mixed upper/lower case.
In addion, you should only have one entry in your DNS server on the Zimbra server and it shoould be like this:
Code:
; generated by /sbin/dhclient-script
search hcjbc.dyndns.org
nameserver 10.100.177.180