Could you give me any more information? My original site (years and years ago) was a PHP monster that got hacked briefly through a security vulnerability in my hosting provider (wasn't my fault, I swear!), so maybe the corporate firewall just has a long memory?

I'll try to get more info when I get time. I'm not really sure what software my place uses for blocking sites. Here's one message I get: "This page has been blocked by the PaloAlto URL filtering device." -- and then it tells me the site is contained in a "malware" category.