How to use an IP when the FQDN exists for a host ?

list Pkc_mls
Mon, 25 Feb 2008 09:06:51 +0100
Message-Id: <user-f6bc6e9eaeb9@xymon.invalid>

Hi all,

I have an entry in my bb-hosts for an smtp server :
1.2.3.4    smtp.domain.com # smtp

but the smtp.domain.com is resolved with a different IP, so the check is 
done with the
IP that comes from the DNS resolution.

is there a way to use the IP ? (I'd like to keep the name).

thanks