Under Debian 7 (x64) I've just done (as root)
Code:
git clone https://github.com/BurntSushi/rtmpdump-ksv
cd rtmpdump-ksv
make
make install
cp librtmp/librtmp.so.1 /usr/lib
Had zero issues with that.
$ make SYS=darwin is recommended in linux/unix environments but I've never needed it.