See bug #35763 for more information.
hey bartron, getspnam's manpage is actually provided by sys-apps/man-pages now -- I've disabled shadow from even installing it any more (though I didn't revision bump shadow) so if you remerge shadow and then upgrade man-pages, you'll get a proper getspnam man page.
Oh... sorry, didn't know that. I originally intended #35763 as some sort of meta-bug to collect man pages with this problem...
bartron -- if you find more (especially in sys-* categories) let me know in one meta bug report -- meanwhile -- what about joining the dev team already?