diff --git a/ChangeLog b/ChangeLog
index 3257370a0..69b273c53 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,7 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* fix alerts.all_categories in python binding
 	* fix torrent-abort issue which would cancel name lookups of other torrents
 	* make torrent file parser reject invalid path elements earlier
 	* fixed piece picker bug when using pad-files
diff --git a/include/libtorrent/alert.hpp b/include/libtorrent/alert.hpp
index a42a3fb2d..8347c9e99 100644
--- a/include/libtorrent/alert.hpp
+++ b/include/libtorrent/alert.hpp
@@ -99,7 +99,11 @@ namespace libtorrent {
 			stats_notification = 0x800,
 			rss_notification = 0x1000,
 
-			all_categories = 0xffffffff
+			// since the enum is signed, make sure this isn't
+			// interpreted as -1. For instance, boost.python
+			// does that and fails when assigning it to an
+			// unsigned parameter.
+			all_categories = 0x7fffffff
 		};
 
 		alert();