diff --git a/configure.ac b/configure.ac
index 1d386f96fe..a1c7df5d7f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1088,6 +1088,14 @@ AG_GST_CHECK_FEATURE(MSDK, [Intel MediaSDK], msdk, [
   [
     AC_DEFINE(HAVE_LIBMFX, 1, [Define if mfx_dispatcher is available])
     HAVE_MSDK="yes"
+    dnl external msdk dispatchers sometimes install headers into prefix/mfx/
+    save_CPPFLAGS="$CPPFLAGS"
+    CPPFLAGS="$LIBMFX_CFLAGS $save_CPPFLAGS"
+    AC_CHECK_HEADER(mfx/mfxdefs.h, [HAVE_MFX_MFXDEFS_H=1], [HAVE_MFX_MFXDEFS_H=0])
+    if test $HAVE_MFX_MFXDEFS_H -eq 1; then
+      AC_DEFINE(HAVE_MFX_MFXDEFS_H, 1, [Define if mfx/mfxdefs.h available])
+    fi
+    CPPFLAGS="$save_CPPFLAGS"
   ], [
     AC_ARG_WITH([msdk-prefix],
             AS_HELP_STRING([--with-msdk-prefix],
diff --git a/sys/msdk/gstmsdkh265dec.c b/sys/msdk/gstmsdkh265dec.c
index f89cf0acc6..66c9e138c6 100644
--- a/sys/msdk/gstmsdkh265dec.c
+++ b/sys/msdk/gstmsdkh265dec.c
@@ -33,7 +33,7 @@
 #  include <config.h>
 #endif
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxplugin.h>
 #else
 #  include "mfxplugin.h"
diff --git a/sys/msdk/gstmsdkh265enc.c b/sys/msdk/gstmsdkh265enc.c
index 7cd39061d6..3ae9bbd257 100644
--- a/sys/msdk/gstmsdkh265enc.c
+++ b/sys/msdk/gstmsdkh265enc.c
@@ -33,7 +33,7 @@
 #  include <config.h>
 #endif
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxplugin.h>
 #else
 #  include "mfxplugin.h"
diff --git a/sys/msdk/gstmsdkmjpegdec.c b/sys/msdk/gstmsdkmjpegdec.c
index ef377751e4..84e00ef3b9 100644
--- a/sys/msdk/gstmsdkmjpegdec.c
+++ b/sys/msdk/gstmsdkmjpegdec.c
@@ -33,7 +33,7 @@
 #  include <config.h>
 #endif
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxstructures.h>
 #  include <mfx/mfxjpeg.h>
 #else
diff --git a/sys/msdk/gstmsdkmjpegenc.c b/sys/msdk/gstmsdkmjpegenc.c
index 00230f8bf5..aed53d2cf4 100644
--- a/sys/msdk/gstmsdkmjpegenc.c
+++ b/sys/msdk/gstmsdkmjpegenc.c
@@ -33,7 +33,7 @@
 #  include <config.h>
 #endif
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxstructures.h>
 #  include <mfx/mfxjpeg.h>
 #else
diff --git a/sys/msdk/gstmsdkvp8dec.c b/sys/msdk/gstmsdkvp8dec.c
index 1b5a1f07de..abe7402329 100644
--- a/sys/msdk/gstmsdkvp8dec.c
+++ b/sys/msdk/gstmsdkvp8dec.c
@@ -34,7 +34,7 @@
 #  include <config.h>
 #endif
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxplugin.h>
 #  include <mfx/mfxvp8.h>
 #else
diff --git a/sys/msdk/gstmsdkvp8enc.c b/sys/msdk/gstmsdkvp8enc.c
index 4c161564fc..bc51ab59e9 100644
--- a/sys/msdk/gstmsdkvp8enc.c
+++ b/sys/msdk/gstmsdkvp8enc.c
@@ -33,7 +33,7 @@
 #  include <config.h>
 #endif
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxplugin.h>
 #  include <mfx/mfxvp8.h>
 #else
diff --git a/sys/msdk/msdk.h b/sys/msdk/msdk.h
index d1c874cbaf..d56bb3a814 100644
--- a/sys/msdk/msdk.h
+++ b/sys/msdk/msdk.h
@@ -41,7 +41,7 @@
 #include <gst/gst.h>
 #include <gst/video/video.h>
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxvideo.h>
 #else
 #  include "mfxvideo.h"
diff --git a/sys/msdk/msdk_libva.h b/sys/msdk/msdk_libva.h
index 9f0187076b..691ea25a00 100644
--- a/sys/msdk/msdk_libva.h
+++ b/sys/msdk/msdk_libva.h
@@ -40,7 +40,7 @@
 #include <gst/gst.h>
 #include <va/va.h>
 
-#ifdef HAVE_LIBMFX
+#ifdef HAVE_MFX_MFXDEFS_H
 #  include <mfx/mfxvideo.h>
 #else
 #  include "mfxvideo.h"