diff --git a/m4/decoders.m4 b/m4/decoders.m4
--- a/m4/decoders.m4
+++ b/m4/decoders.m4
@@ -290,7 +290,9 @@ AC_DEFUN([XINE_DECODER_PLUGINS], [
         if test x"$enable_musepack" != x"internal"; then
             AC_CHECK_LIB([mpcdec], [mpc_decoder_decode],
                          [AC_CHECK_HEADERS([mpcdec/mpcdec.h], [have_external_libmpcdec=yes], [have_external_libmpcdec=no])],
-                         [have_external_libmpcdec=no])
+                         [AC_CHECK_LIB([mpcdec], [mpc_decoder_decode_frame],
+                                       [AC_CHECK_HEADERS([mpc/mpcdec.h], [have_external_libmpcdec=yes], [have_external_libmpcdec=no])],
+                                       [have_external_libmpcdec=no])])
             if test x"$have_external_libmpcdec" != x"yes"; then
                 AC_MSG_RESULT([*** no usable version of libmpcdec found, using internal copy ***])
             else
diff --git a/src/combined/Makefile.am b/src/combined/Makefile.am
--- a/src/combined/Makefile.am
+++ b/src/combined/Makefile.am
@@ -42,6 +42,7 @@ xineplug_musepack_la_DEPENDENCIES = $(MP
 xineplug_musepack_la_DEPENDENCIES = $(MPCDEC_DEPS)
 xineplug_musepack_la_LIBADD = $(XINE_LIB) $(LTLIBINTL) $(MPCDEC_LIBS)
 xineplug_musepack_la_CFLAGS = $(AM_CFLAGS) $(MPCDEC_CFLAGS)
+xineplug_musepack_la_CPPFLAGS = $(AM_CPPFLAGS) -I$(top_srcdir)/src/demuxers
 
 xineplug_flac_la_SOURCES = flac_demuxer.c flac_decoder.c
 xineplug_flac_la_LIBADD = $(XINE_LIB) $(LIBFLAC_LIBS)