Index: Portfile
===================================================================
--- Portfile	(revision 57111)
+++ Portfile	(working copy)
@@ -4,8 +4,8 @@
 PortSystem 1.0
 
 name            ffmpeg-devel
-set svn_rev     19723
-set swscale_rev 29548
+set svn_rev     19787
+set swscale_rev 29652
 version         ${svn_rev}
 categories      multimedia
 maintainers     devans openmaintainer
@@ -141,12 +141,14 @@
     depends_lib-delete path:lib/pkgconfig/sdl.pc:libsdl
     depends_lib-append path:lib/pkgconfig/sdl.pc:libsdl-devel
     # ticket #20938
-    if { ![variant_isset no_gpl] } {
-        configure.args-delete --enable-swscale
+    if { [info exists build_arch] && $build_arch == "i386" } {
+        if { ![variant_isset no_gpl] } {
+            configure.args-delete --enable-swscale
+        }
+        if { ![variant_isset no_mmx] } {
+            configure.args-append --disable-mmx --disable-mmx2 --disable-sse --disable-ssse3 --disable-amd3dnow --disable-amd3dnowext
+        }
     }
-    if { ![variant_isset no_mmx] } {
-        configure.args-append --disable-mmx --disable-mmx2 --disable-sse --disable-ssse3 --disable-amd3dnow --disable-amd3dnowext
-    }
 }
 
 variant no_mmx description {disable all x86 asm optimizations} {