From: Ryan Niebur <ryan@freegeek.org>

This patch is needed for compatibility with newer versions of libav.
Starting with version 0.8, avutil.h does not include mathematics.h.

Index: zoneminder/src/zm_ffmpeg.h
===================================================================
--- zoneminder.orig/src/zm_ffmpeg.h	2012-01-15 13:13:54.000000000 -0800
+++ zoneminder/src/zm_ffmpeg.h	2012-01-15 13:16:42.000000000 -0800
@@ -31,6 +31,7 @@
 #endif
 #if HAVE_LIBAVUTIL_AVUTIL_H
 #include <libavutil/avutil.h>
+#include <libavutil/mathematics.h>
 #endif
 #if HAVE_LIBAVCODEC_AVCODEC_H
 #include <libavcodec/avcodec.h>