Could you please open Terminal.app and type the following command into it, and copy and paste the result here?
traceroute www.actionsforge.com
This should show where it’s going off the rails. Either you will be unable to resolve the base domain name, or you will be able to resolve it (DNS lookup works) but you won’t be able to get there from where you are (the trace will devolve into a series of lines filled with asterisks).
Okay, you’re hitting the right server, and you’re getting all the way to just outside their data center, so something odd is happening in the last mile. The fact that I can see the server from here is quite anomalous, with the error happening literally on their doorstep. Is there any chance that your domain or IP range is blacklisted somewhere? You might be tarred with the same brush, and be kicked out by their various border routers.
I’ll pass this trace on to Joyent and see what they make of it. Could you also post your current IP address? Do you know if your provider uses a floating range of addresses or do you have a static IP address?