diff -aurN devel/simgear.orig/Makefile devel/simgear/Makefile
--- devel/simgear.orig/Makefile	2009-02-12 08:04:22.389825704 +0100
+++ devel/simgear/Makefile	2009-02-12 08:05:06.964157776 +0100
@@ -19,9 +19,14 @@
 LIB_DEPENDS=	openal.0:${PORTSDIR}/audio/openal \
 		jpeg.9:${PORTSDIR}/graphics/jpeg \
 		alut.1:${PORTSDIR}/audio/freealut \
-		osg.48:${PORTSDIR}/graphics/osg \
 		boost_thread.4:${PORTSDIR}/devel/boost
 
+.if defined(WITH_OSG_DEVEL)
+LIB_DEPENDS+=	osg.54:${PORTSDIR}/graphics/osg-devel
+.else
+LIB_DEPENDS+=	osg.48:${PORTSDIR}/graphics/osg
+.endif
+
 USE_XORG=	ice sm x11 xext xi xt xmu
 USE_GL=		gl glu glut
 GNU_CONFIGURE=	yes
diff -aurN games/flightgear.orig/Makefile games/flightgear/Makefile
--- games/flightgear.orig/Makefile	2009-02-12 07:57:30.117028183 +0100
+++ games/flightgear/Makefile	2009-02-12 08:03:57.635199766 +0100
@@ -22,7 +22,6 @@
 COMMENT=	The FlightGear flight simulator
 
 LIB_DEPENDS=	openal.0:${PORTSDIR}/audio/openal \
-		osg.48:${PORTSDIR}/graphics/osg \
 		boost_thread.4:${PORTSDIR}/devel/boost
 BUILD_DEPENDS=	${LOCALBASE}/lib/libplibsl.a:${PORTSDIR}/x11-toolkits/plib \
 		${LOCALBASE}/lib/libsgmisc.a:${PORTSDIR}/devel/simgear
@@ -30,6 +29,12 @@
 		${LOCALBASE}/lib/libsgmisc.a:${PORTSDIR}/devel/simgear \
 		${LOCALBASE}/share/FlightGear/version:${PORTSDIR}/games/flightgear-data
 
+.if defined(WITH_OSG_DEVEL)
+LIB_DEPENDS+=	osg.54:${PORTSDIR}/graphics/osg-devel
+.else
+LIB_DEPENDS+=	osg.48:${PORTSDIR}/graphics/osg
+.endif
+
 USE_XORG=	ice sm x11 xext xi xt xmu
 USE_GL=		gl glu glut
 USE_GMAKE=	yes