Can't access this site

[#1]

I can no longer access http://www.the-enlightened-voice.co.uk/
The people who host this forum say it's an ISP problem because, as they put it:
A small number of UK users will experience issues accessing any freeforums.org forum. A number of UK ISPs (including but not limited to Virgin Media, Sky Broadband, BT, O2, 3 Networks) recently started routing some traffic to freeforums.org through a transparent proxy.
Transparent proxies pose problems on our forum software. These problems range from posting problems to security issues. As a result, until the transparent proxies are removed from these users, we are unable to serve them on freeforums.org.
The only solution to this is having the transparent proxy removed from their traffic. We recommended urging members to call up their ISP as well and complain if they are having issues accessing your forum.
Can anyone confirm that this is true?

[#2]

Whilst PN will be along shortly to deny they use any proxies, transparent or otherwise, all traffic which is heading for a site (or IP address) on the IWF blacklist is routed through a transparent proxy to filter out any indecent images.
Untill freeforums.org get them selves removed from the IWF blacklist, there will be no resolution to this.

Quote

The remote host or network may be down. Please try the request again. Generated Wed, 02 Feb 2011 16:06:06 GMT by pcl-iwfcache03.plus.net (squid)

(emphasis mine)