As the summary states, wine should depend on emul-linux-x86-soundlibs[pulseaudio] when building 32-bit version on amd64 with USE=pulseaudio enabled.
http://sources.gentoo.org/app-emulation/wine/wine-1.2.ebuild?r1=1.7&r2=1.8 http://sources.gentoo.org/app-emulation/wine/wine-1.2.1.ebuild?r1=1.3&r2=1.4 http://sources.gentoo.org/app-emulation/wine/wine-1.2.2.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/app-emulation/wine/wine-1.3.0.ebuild?r1=1.8&r2=1.9 http://sources.gentoo.org/app-emulation/wine/wine-1.3.1.ebuild?r1=1.6&r2=1.7 http://sources.gentoo.org/app-emulation/wine/wine-1.3.2.ebuild?r1=1.8&r2=1.9 http://sources.gentoo.org/app-emulation/wine/wine-1.3.3.ebuild?r1=1.5&r2=1.6 http://sources.gentoo.org/app-emulation/wine/wine-1.3.4.ebuild?r1=1.4&r2=1.5 http://sources.gentoo.org/app-emulation/wine/wine-1.3.5.ebuild?r1=1.3&r2=1.4 http://sources.gentoo.org/app-emulation/wine/wine-1.3.6.ebuild?r1=1.3&r2=1.4 http://sources.gentoo.org/app-emulation/wine/wine-1.3.7.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/app-emulation/wine/wine-1.3.8.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/app-emulation/wine/wine-1.3.9.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/app-emulation/wine/wine-1.3.10.ebuild?r1=1.3&r2=1.4 http://sources.gentoo.org/app-emulation/wine/wine-1.3.11.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/app-emulation/wine/wine-9999.ebuild?r1=1.70&r2=1.71