Site is not accessible - infected with 'HTML:Script-inf'

I’ve been trying to connect to http://www.hyperjapan.co.uk but got a message saying that the site was infected with ‘HTML:Script-inf’

I have contacted the owners of the site but they have said that there is nothing wrong with their site and that it is a problem on my PC. I assume that Avast is blocking the site for a valid reason but don’t know what that is and therefore don’t know if it is safe to ignore the warning of Avast.

Is anyone able to help me?

http://sitecheck.sucuri.net/results/www.hyperjapan.co.uk/
http://labs.sucuri.net/db/malware/mwjs-include-rebots?v7

Wepawet gives this site as suspicious: http://wepawet.iseclab.org/view.php?hash=c7b9274c1f9aa74f60c12c15f7ce50fc&t=1366987504&type=js
Malware details from Sucuri’s explained: http://labs.sucuri.net/?details=cep40.ca has Sucuri Blacklist Status
What goes on from that redirect IP: https://www.virustotal.com/en/ip-address/76.74.128.10/information/

polonus