* configure.ac.in: print an error message if libmpeg2 is not found or too old.

configure.ac.in

@@ -1761,7 +1761,7 @@ then
         LDFLAGS_a52tofloat32="${LDFLAGS_test} -la52 ${LDFLAGS_a52tofloat32}"
         CPPFLAGS_a52tofloat32="${CPPFLAGS_a52tofloat32} ${CPPFLAGS_test}"
       ],[
-        AC_MSG_ERROR([Could not find a52 on your system: you may get it from http://liba52.sf.net/. Alternatively you can use --disable-a52 to disable the a52 plugin.])
+        AC_MSG_ERROR([Could not find liba52 on your system: you may get it from http://liba52.sf.net/. Alternatively you can use --disable-a52 to disable the a52 plugin.])
       ])
     ])
     CPPFLAGS="${CPPFLAGS_save}"
@@ -1814,9 +1814,11 @@ then
       [AC_MSG_RESULT([yes])
         PLUGINS="${PLUGINS} libmpeg2"
         LDFLAGS_libmpeg2="${LDFLAGS_libmpeg2} -lmpeg2"],
-      [AC_MSG_RESULT([no]) ]
+      [AC_MSG_RESULT([no])
+        AC_MSG_ERROR([Your libmpeg2 is too old (you need the cvs version): you may get a more recent one from http://libmpeg2.sf.net/. Alternatively you can use --disable-libmpeg2 to disable the libmpeg2 plugin.])])],
+
+    [AC_MSG_ERROR([Could not find libmpeg2 on your system: you may get it from http://libmpeg2.sf.net/ (you need the cvs version). Alternatively you can use --disable-libmpeg2 to disable the libmpeg2 plugin.])]
   )
-  ])
 fi
 
 dnl