This will probably be an easy one (hopefully!) for you guys. I've
never had to deal with something like this so I'm going to ask in the

Easiest way for me to make this example would be as follows:

[a] Our customer owns
[b] He does not host an internal web server, so another company hosts
it for him, which we will be changing - just not yet.

[c] Sometimes the www. address on the other end (ISP hosting it)

This causes them to not be able to contact their www server anymore.
I think I can do something with a PTR to help this process can't I?
Right now, I was using a DNS A record to point it at the right
external address, but this is a pain when it changes, as I have to
manually update it.

www. doesn't resolve to anything internal, and they use internal DNS.
So if they cannot resolve it internally, my understanding (same as MS
DNS) is that it won't query Root servers or anything because you are
trying to resolve a name that exists on the same domain that DNS is
setup on.

I'm just curious if there's a way to make a record that will somehow
grab the external IP and make the update in DNS somehow.

Thanks for any help!