works for me, could be your ISP has a bad address in for the URL in the DNS.

Non-authoritative answer:
Name:    forums.polyloop.net
Address:  91.121.153.174

is what I get from nslookup forums.polyloop.net

That or your tool bar is intercepting something perhaps, or you have a broken route to their host.  It is pingable as well.

Pinging forums.polyloop.net [91.121.153.174] with 32 bytes of data:
Reply from 91.121.153.174: bytes=32 time=171ms TTL=55
Reply from 91.121.153.174: bytes=32 time=168ms TTL=55

Ping statistics for 91.121.153.174:
    Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 168ms, Maximum = 171ms, Average = 169ms

Let us know if either of those work for you.