--- a/config/autoconf.mk.in
+++ b/config/autoconf.mk.in
@@ -219,17 +219,17 @@ MOZ_HUNSPELL_LIBS = @MOZ_HUNSPELL_LIBS@
 MOZ_HUNSPELL_CFLAGS = @MOZ_HUNSPELL_CFLAGS@
 
 MOZ_NATIVE_LIBEVENT = @MOZ_NATIVE_LIBEVENT@
 MOZ_LIBEVENT_LIBS = @MOZ_LIBEVENT_LIBS@
 MOZ_LIBEVENT_INCLUDES = @MOZ_LIBEVENT_INCLUDES@
 
 MOZ_NATIVE_LIBVPX = @MOZ_NATIVE_LIBVPX@
 MOZ_LIBVPX_LIBS = @MOZ_LIBVPX_LIBS@
-MOZ_LIBVPX_INCLUDES = @MOZ_LIBVPX_INCLUDES@
+MOZ_LIBVPX_CFLAGS = @MOZ_LIBVPX_CFLAGS@
 
 MOZ_NATIVE_ZLIB	= @MOZ_NATIVE_ZLIB@
 MOZ_NATIVE_BZ2	= @MOZ_NATIVE_BZ2@
 MOZ_NATIVE_JPEG	= @MOZ_NATIVE_JPEG@
 MOZ_NATIVE_PNG	= @MOZ_NATIVE_PNG@
 MOZ_TREE_CAIRO = @MOZ_TREE_CAIRO@
 MOZ_TREE_PIXMAN = @MOZ_TREE_PIXMAN@
 

--- a/configure.in
+++ b/configure.in
@@ -5346,45 +5346,47 @@ if test -n "$MOZ_OMX_PLUGIN"; then
 fi
 
 dnl system libvpx Support
 dnl ========================================================
 MOZ_ARG_WITH_BOOL(system-libvpx,
 [  --with-system-libvpx    Use system libvpx (located with pkgconfig)],
     MOZ_NATIVE_LIBVPX=1)
 
-MOZ_LIBVPX_INCLUDES=
+MOZ_LIBVPX_CFLAGS=
 MOZ_LIBVPX_LIBS=
 
 if test -n "$MOZ_VP8"; then
     AC_DEFINE(MOZ_VP8)
     if test -n "$MOZ_VP8_ERROR_CONCEALMENT" ; then
         AC_DEFINE(MOZ_VP8_ERROR_CONCEALMENT)
     fi
     if test -n "$MOZ_VP8_ENCODER" ; then
         AC_DEFINE(MOZ_VP8_ENCODER)
     fi
 
     if test -n "$MOZ_NATIVE_LIBVPX"; then
         dnl ============================
         dnl === libvpx Version check ===
         dnl ============================
         dnl Check to see if we have a system libvpx package.
-        PKG_CHECK_MODULES(LIBVPX, vpx >= 1.0.0)
+        PKG_CHECK_MODULES(MOZ_LIBVPX, vpx >= 1.0.0)
 
         MOZ_CHECK_HEADER([vpx/vpx_decoder.h], [], 
          [AC_MSG_ERROR([Couldn't find vpx/vpx_decoder.h which is required for build with system libvpx. Use --without-system-libvpx to build with in-tree libvpx.])])
 
+        _SAVE_LIBS=$LIBS
         AC_CHECK_LIB(vpx, vpx_codec_dec_init_ver, [], 
          [AC_MSG_ERROR([--with-system-libvpx requested but symbol vpx_codec_dec_init_ver not found])])
+        LIBS=$_SAVE_LIBS
     fi
 fi
 
 AC_SUBST(MOZ_NATIVE_LIBVPX)
-AC_SUBST(MOZ_LIBVPX_INCLUDES)
+AC_SUBST(MOZ_LIBVPX_CFLAGS)
 AC_SUBST(MOZ_LIBVPX_LIBS)
 
 if test "$MOZ_WEBM"; then
     MOZ_SYDNEYAUDIO=1
     MOZ_CUBEB=1
     MOZ_MEDIA=1
     case "$target_cpu" in
     arm*)

--- a/content/media/webm/Makefile.in
+++ b/content/media/webm/Makefile.in
@@ -25,10 +25,10 @@ CPPSRCS		= \
 		nsWebMReader.cpp \
 		$(NULL)
 
 FORCE_STATIC_LIB = 1
 
 include $(topsrcdir)/config/rules.mk
 
 LOCAL_INCLUDES = \
-		$(MOZ_LIBVPX_INCLUDES) \
+		$(MOZ_LIBVPX_CFLAGS) \
 		$(NULL)