There are two problems...well maybe three.
First off, the SAVVIS accounts are apparently guilty by association. They are on a server that apparently has a "history" and any one on that server becomes guilty by association when it comes to most spam programs, or IP blockers. IOW they are on a guilty server or at least one that was. Second, when you click on a link at a legit site you end up connected to that address, not the one that contained the link, which is why it is still blocked.

Contrary to some comments you don't have to quit using PG IF it is blocking a site you wish to visit. Simply open PG, and look at the IPs displayed on the "protection page". This is a whole lot easier if you tell it not to display allowed connections. When the ip comes up that you wish to visit, high light it, right click and select allow. You can allow it for 15 minutes, one hour or permanently. You can also copy that IP to the clipboard.

Oft times legit businesses pick an ISP not knowing their past and find they are having problems. Some times a legit ISP ends up with an IP, or range of reissued IPs that were used for spamming. It sometimes takes a while for the addresses to get cleared (off the black lists)

AND sometimes some customers PCs will become infected, start spewing spam and *everyone* on that ISP will suddenly find themselves blocked. Recently I couldn't get to my own mail accounts. The problem? A number of the customers on that ISP had their computers infected and were spewing spam. The whole block of addresses were blocked by a number of sites and applications.

PG works well, but no computer connected to the Internet is completely safe from those who know how to get in. Remember too, that when file sharing the other end usually needs to have your address to be able to share files.