I don't have an answer for you, but I was going to make the address in your post active and realized that it didn't work. I Googled "Pop3Hot" and came up with http://pop3hot.com I'm fairly certain this is the same program you were asking about.
To make a link active you can use the 1-Click TagPanel on your post page or simply surround the url with <!t><!/t> and <!t><!/t>.
FYI from the website I read:<hr>All Pop3Hot functionality -and more- has recently been merged into IzyMail. Pop3Hot is no longer available for download.<hr>have fun