diff --git a/TODO b/TODO
index f8147b19..a34d95fa 100644
--- a/TODO
+++ b/TODO
@@ -255,6 +255,16 @@ existing messages at the next database upgrade).
 Add support for the user to specify custom headers to be indexed (and
 re-index these for existing messages at the next database upgrade).
 
+Build system
+------------
+Fix to allow a non-source-directory build. For example, the below
+should be made to work:
+
+	mkdir build_dir
+	cd build_dir
+	../configure
+	make
+
 Test suite
 ----------
 Achieve 100% test coverage with the test suite.