DNS Configuration issue

There's this problem I've been having for some time.

I have a small server (http, mstsc, file-, ...) at home. It has a real IP address. It also acts as a gateway (AP, lan, bluetooth lan) and shares it's internet connectivity. For that reason that machine acts as a DNS and a DHCP server and has an internal IP address.

There's a domain name resolving to the external (real) IP address.

The problem is seeing the the stuff that should be seen from the outside world from the internal network. All that stuff works when using the internal IP to access that machine, so it's not a firewall issue.

What works and what not: pinging the external address works, telnetting to external IP:80 fails as with any other port.

A simple site wouldn't mind internal or external address.
My blogging application on the contrary would fail because the resources (pictures) are with FQN URLs.
And I would like to make this work in a pretty way.

One solution - local DNS server supplying the internal IP address for that domain name.
This works now, but my local DNS has to have an entry for every single domain/sub-domain - this approach sucks. I also have different services exported on the two different IPs and this local DNS approach break that.

I have seen this problem with the networks of midsize companies. Example with deploying a product inside that network (have to supply internal names).

I'm looking for a better solution.

Anyone?