IIS 6.0 error on windows 2003

Hi,

I am running windows 2003 server and i have IIS 6.0 installed on it. The problem i am facing is that i have multiple websites on my IIS and i have also loaded virtual IP’s. But still for some reason the website pointed to the main gateway IP works and the other websites dont work at all, if i try to open the website form my computer the website opens and if i try to open the website from any remote location the website dosent open. I have ISA server installed on my computer and i also have norton internet security. The firewall is not causing any problem as i disabled the firewall once and still the website dont work.
Any idea anyone?
Please help.

Regards.