HTTP GET Request Times Out

I have a program running in Smallworld GIS that makes OpenStreetMap.org maps available as a backdrop. The program works for the vendor but not at my site. I can access OpenStreetMap.org maps from Internet Explorer just fine. I've dug down into the Smallworld api calls and found the method that makes the HTTP request. When I manually invoke the method to get data from other places, it works, but with OpenStreetMap.org it times out. I changed the HTTP GET request to HEAD, it works fine. Below is printed return information from a HEAD request:

HTTP Port # 80
Setting up TCPIP Connection...
Local address: 131.191.187.166. port 1203
Remote address: 129.132.168.206. port 80
TCP Connection Result: HTTP/1.1 200 OK
Date: Tue, 22 Feb 2011 20:21:24 GMT
Server: Apache/2.2.3 (CentOS)
Cache-Control: max-age=10800
Last-Modified: Mon, 15 Nov 2010 08:56:07 GMT
Content-Length: 21013
Connection: close
Content-Type: image/png

I've tried accessing OpenStreetMap.org maps from telnet and it times out as well:

jfarmer@smtp001:~$ telnet 129.132.168.206 80
Trying 129.132.168.206...
Connected to 129.132.168.206.
Escape character is '^]'.
GET / HTTP/1.0

And there it will sit for about 5 minutes, until the connection is closed by the remote host.

I suspect that this problem is very unique but hope someone may have an idea of what is going on.