diff -ruN /usr/ports/lang/basic256/Makefile lang/basic256/Makefile
--- /usr/ports/lang/basic256/Makefile	2013-11-23 17:52:29.000000000 +0100
+++ lang/basic256/Makefile	2013-11-27 18:22:10.000000000 +0100
@@ -24,6 +24,10 @@
 
 MAKE_JOBS_UNSAFE=	yes
 
+do-configure:
+	@cd ${WRKSRC} && ${SETENV} ${CONFIGURE_ENV} \
+	${QMAKE} "PREFIX=${PREFIX}" BASIC256.pro
+
 post-patch:
 	@${REINPLACE_CMD} -e 's/mutex/mymutex/' ${WRKSRC}/*.cpp
 	@${REINPLACE_CMD} -e 's|%%LOCALBASE%%|${LOCALBASE}|' ${WRKSRC}/BASIC256.pro