My Apache Webserver is publicly accessible only from certain IP addresses

I am hosting through optimum online and it seems as if only users with optimum online IP addresses can see my website on their computers. The site is being hosted through a port other than the standard port 80. the website is: getwhatUwant.com

Can anyone give me an idea of why this may be happening? I can access my website from my own computer, and anyone (seemingly) with optimum online can also access my website. Most people who do not have optimum online can not see my website on their computers. When I try to connect to my webserver from my own computer through an anonymous proxy (obtained from proxy4free.com), I am unable to see my website on my own computer!

WEBSERVER IP ADDRESS: 24.187.119.190:65254

APACHE 2.05
SUN ONE ASP 4.0.0.2
PHP 5
MYSQL 5.1
FREE DNS SERVICE PROVIDED BY SITELUTIONS.COM

THe computer is connected directly to the internet and is part of a windows xp home network in which all computers are connected by a HUB (not a router).

If someone can help me out here, I will very greatly appreciate it. I spent so much time developing my website only to find that it is not accessible to anyone who does not use optimum online as their ISP. Please let me know how i can fix this problem and give me some hints as to what may be causing it. THanks