You'll probably need to add the 'name' to your own hosts file in order to see it, until/unless the DNS service you mentioned becomes updated and its results available to you.
Adding something like this may help:
Code:
87.24.162.110 zen.100asa.it
This post talks about where your hosts file is located:
http://www.zen-cart.com/forum/showpo...41&postcount=8
But, then again, I'm not certain whether the 3rd-party DNS service will work to allow everyone else access properly either ... the routing of a subdomain should be done by the hosting company server where your main domain is hosted ... otherwise you may end up with circular loops of confusion trying to determine which destination is truly valid.
ie: *.100asa.it = host IP address
and zen.100asa.it = a different IP address
If you're going to do that, then you should be customizing the DNS settings on your host's server, not via a 3rd-party DNS service.