How to install wine on Darwin-*-amd64 (multiarch/universal support)

[Xiyue Deng <manphiz%gmail.com@localhost>]

Hi,

When trying to install wine in pkgsrc bootstrapped on Darwin amd64, it
fails with the following message:

----------8<----------

$ cd $HOME/pkgsrc/emulators/wine
$ time bmake install
ERROR: This package is only available for these platforms: *-*-i386.
ERROR: This package has set PKG_FAIL_REASON:
ERROR: wine-1.6.2nb2 is not available for Darwin-13.2.0-x86_64
*** Error code 1

Stop.
bmake: stopped in /Users/dxy/pkgsrc/emulators/wine

----------8<----------

I wonder whether there is a way to workaround this restriction. Is
there a way to enable universal binary support on Darwin or force
build i386 port which it obviously supports?

Thanks in advance.