problem with OSX safari (webkit)

[jart]

My guess is: it's forwarding requests to itself, creating an infinite loop. Although it should not lock up completely in this case, so maybe it's something different.
Forwarding to itself can happen like this:
You already had your "Automatic" (or whatever) profile set to use bfilter by manually setting the proxy settings. Then bfilter's installer created a "(BF) Automatic" profile for you, configuring it to use bfilter, and to forward requests wherever "Automatic" was forwarding them, that is to bfilter again.
Yes, I should have mentioned in the docs that you are not supposed to modify system-wide proxy settings in case of the OSX version.
So, if I am right about the source of the problem, you should go to network preferences and disable http proxy for the "Automatic" profile.