http to port 80 terrible slow with browser but to 8443 fast!

[jussio]

Plesk 8.1 is running on RHEL 4 ES. RHEL runs under Microsoft Virtual server/Windows 2003. Server is HP 145 DL / 2 x 2.8 XEON with 2 gigs of memory. Everything is allmost ok... only problem is that when I try to browse pages with IE Explorer, Firefox etc.. it will take 2 to 5 minutes to load page. Plesk control panel is normal and fast. If I telnet to port 80 and I send GET / HTTP/1.0 to server I will get full page in about 1 second. I have checked our firewall and all the setting over 10 times. I am allmost pulling my hair off....

Edit:

Without Plesk pages loads smoothly. So it must be Plesk issue maybe problem is that we use other virtualization program than Virtuozzo

 

[jussio]

Now I know what is wrong....

Telnet to port 80 was fast because it just shows text. So I was so studid that I did not try it with other than default PLESK page. I do not know what is wrong with default page but when I tryed with real content everything was ok. I even tryed it with my Nokia E61 and it seems that photos taked too much time load.