In both the pulseaudio-0.9.17 and -0.9.17-r50 ebuilds, there is a line if use hal && !use udev; then That needs to be if use hal && ! use udev; then for bash to parse it properly.
22 Sep 2009; Diego E. Pettenò <flameeyes@gentoo.org> pulseaudio-0.9.17.ebuild, pulseaudio-0.9.17-r50.ebuild: Fix !use missing whitespace.