is it possible?
subsequest to my previous question (
I want to ask one more question
Can we configure "intranet.theirDomain.com" with local IP address for any other zone?
If there is ".com" within the url then it can't be configured for InTRAnet?
The names for the zones don't matter. You could use the 'extranet' zone for another intranet name if you wanted, the names are just to make it a bit more friendly for beginners.
What you describe sounds routine, you create a web application with a name, then use an AAM to allow users to access it with a more friendly name. Frequently you end up creating http://intranet.domain.com and http://intranet as an AAM, or vice versa.
You can use .com for an intranet site, you would need to add the site as an A Host record in your DNS server so that traffic is sent to your internal server rather than out into the wider world.