From the README

(Based on reading the BSD ipfw manpage, this rule ought to work on BSD: ipfw add 40 fwd 127.0.0.1,1935 tcp from any to any 1935 not uid proxy Some confirmation from any BSD users would be nice.) (We have a solution for Windows based on a TDI driver; this is known to work on Win2K and WinXP but is assumed to not work on Vista or Win7 as the TDI is no longer used on those OS versions. Also, none of the known solutions are available as freeware.)

I took a crack at ipfw for Windows a while back but I stopped because the one I found only had a 32-bit build http://sourceforge.net/projects/wipfw/files/experimental It turns out theres is another open source implementation of ipfw here http://info.iet.unipi.it/~luigi/dummynet The site notes both 64-bit and 32-bit support for Windows 7. I successfully installed it for Windows 7 64-bit, detailed here http://stackoverflow.com/a/12719202 However the next challenge is running 2 users. Apparently Cygwin "su" has never worked http://cygwin.com/faq-nochunks.html#faq.using.su and the suggested workaround is to install "sshd". I gave up at this point, but I thought I would share my findings. Currently I am using "RtmpDumpHelper" to capture streams but with "ipfw" we could have an open source solution.