diff --git a/devel/gdb6/Makefile b/devel/gdb6/Makefile
index 2ee5c8f73757..edade1801388 100644
--- a/devel/gdb6/Makefile
+++ b/devel/gdb6/Makefile
@@ -37,10 +37,12 @@ VER=	${PORTVERSION:S/.//}
 PLIST_SUB=	VER=${VER}
 MAN1=	gdb${VER}.1
 
-#ONLY_FOR_ARCHS=	i386 amd64	# untested elsewhere, might work
-
 .include <bsd.port.pre.mk>
 
+.if ${ARCH} == "ia64" || ${ARCH} == "powerpc" || ${ARCH} == "sparc64"
+BROKEN=		Does not configure on ia64, powerpc, or sparc64
+.endif
+
 .if defined(WITH_INSIGHT)
 LIB_DEPENDS=	itk:${PORTSDIR}/x11-toolkits/itk
 RUN_DEPENDS=	${LOCALBASE}/lib/iwidgets:${PORTSDIR}/x11-toolkits/iwidgets
diff --git a/mail/milter-skem/Makefile b/mail/milter-skem/Makefile
index f77dff599573..3e1c9b065057 100644
--- a/mail/milter-skem/Makefile
+++ b/mail/milter-skem/Makefile
@@ -30,6 +30,10 @@ post-install:
 
 .include <bsd.port.pre.mk>
 
+.if ${ARCH} == "powerpc"
+BROKEN=		Does not compile on powerpc
+.endif
+
 .if ${OSVERSION} >= 700011
 EXTRA_PATCHES=  files/timet.patch
 .endif