Steven! I can't set up a subscription to a podcast I'm paying for, either, and I don't have any weird characters in my User Name.
Installed the patch up there, right-clicked "Podcasts"/"New Subscription", pasted in the url and tried to use the "user name" and "password" boxes at the bottom of the "Create Subscription" box, but it doesn't even wait for me to fill them in.
The second I click anywhere else out of the box for the URL, the red exclamation mark pops up, and if I hover over it, it tells me that it was "unable to verify the validity of this url - the remote server returned an error: (401) Unauthorized." Then I fill in the user info boxes and nothing happens.
I even tried the "http://(UserName):(password)@(the rss feed site)" technique, but that didn't work either! Any ideas? Thanks, and let me know if you need a temporary account to figure this out and I'll try to get one for you.