Since that are both associated with the same IP address, I can only assume that it is the IP address that is blocked. This is usually because one or more domains on that IP are infected so all are currently blocked.
The villekuis-software.info site appears to be empty and not much on finexthosting.info according to sucuri.net. So similar results from urlquery, but the associated domains on that IP address raise some concern. The best you can hope for is unblocking the IP and blocking any specific domains that are infected.
There is an on-line contact form, http://www.avast.com/contact-form.php?loadStyles for: * Sales inquiries; Technical issues; Website issues; Report false virus alert in file; Report false virus alert on website; Undetected Malware; Press (Media), issues.
If you are reporting an FP, then you get another input field open (image3), click Browse button and navigate to the file or enter the web URL for the site you wish to submit for review, etc. A link to this topic also wouldn’t hurt.