Question : How to set up Forest to Forest Domain Trust through VPN with Windows Server 2003?

Hello,
I've been working on setting up a Forest to Forest Domain Trust between two separate physical locations connected by VPN.  However, the Domains are still not able to see each other and resolve names via DNS.  Following are the steps I've come across in my research and have taken thus far:

1.  Raised the Domain Functional Level from Windows 2000 Mixed to Windows 2000 Native.  The Forest Functional Level is Windows 2000
2.  Added Secondary Zones to both DNS servers
3.  Set to 'allow zone transfers' on both DNS Servers
4.  I've opened the following ports on my CISCO 1841 router - 135,389,636,3268,3269,53, and 445.  There is a range of TCP ports 1024 - 65535 that I have not opened because I do not see how to do this in the GUI Administration Software for the router.  Also, didn't open TCP/UDP 88 because didn't think I needed to since running Windows Server 2003.

What am I missing here?  Any help is appreciated.

Answer : How to set up Forest to Forest Domain Trust through VPN with Windows Server 2003?

Another way I just thought of would be to setup fowarders.  This may be much simpler than what you're trying to do with replicating domains.

From http://support.microsoft.com/kb/300202

1. In DNS Manager, right-click the DNS Server object, and then click Properties.
2. Click the Forwarders tab.
3. Click to select the Enable Forwarders check box.
4. In the IP address box, type the first DNS server to which you want to forward, and then click Add.

The problem is that if you do this on both domains, internet access will NOT work.  Try this during a downtime window.  If both domains can see each other, join the domains into the same forest, then make sure AD-integrated zones are set to replicate to all DNS servers in the forest.  Then you can undo the fowarders and Intenet DNS should work again.