Window Maker has been added as one of the unsupported desktop environments for PC-BSD 9.1.
As far as I know, Elightenment (E17) needs to be recompiled every time you want to change a configuration option. This does not make it a good choice for us to add a system-package for it, because everyone will probably need to recompile it to "get it right" anyway. If this ever does change for Enlightenment (needing to recompile to configure), please let me know and I can get that added as an additional DE as well. For now, you will have to add it in yourself using the FreeBSD ports tree.
~ Ken Moore ~