Message Invalid host object directive 'check_dummy&#039

Hi Friends,

i’ve got a Problem in configure my Nagios…
I want to check a SMTP Service with Nagios… This check is successful but the Srever is not reachable for PING Packets so that the Host is masked as DOWN…

I looked for a Resolve and i found the check_dummy Command.
I have integrated this in my define host directive.

[blockquote]
define host {
use comp_templ
host_name mx.e…net
alias MX1
address mx.e…net
hostgroups MX Check
check_dummy 0
}
[/blockquote]

Can you tell me, what is here the Problem?
The exactly Failure Message is the following:

Error: Invalid host object directive ‘check_dummy’.
Error: Could not add object property in file ‘/usr/local/nagios/etc/objects/checksmtp.cfg’ on line 15.

I hope you can help me…
Thanks in advance…

Best Regards
Marc