It has been observed that the target config-recursive for emulators/i386-wine-devel can cause bsd.port.mk to be included twice when run in i386 jails. This seems to be due to the fact that config-recursive ignores PKGNAMEPREFIX definition, which is used in emulators/wine-devel to test wether bsd.port.[pre|post.]mk needs to be included or bsd.port.mk has already been included by i386-wine-devel. We change the testing variable to _POSTMKINCLUDED, which is the variable used by bsd.port.mk at line 1580.