We actually do want tmux.conf to go into ${prefix}/etc,
since the real /etc is not writeable on Android.

diff -u -r ../tmux-1.9a/configure ./configure
--- ../tmux-1.9a/configure	2014-02-22 21:56:15.000000000 +0100
+++ ./configure	2014-02-24 08:50:16.000000000 +0100
@@ -4011,7 +4011,7 @@
 
 
 # Default tmux.conf goes in /etc not ${prefix}/etc.
-test "$sysconfdir" = '${prefix}/etc' && sysconfdir=/etc
+#test "$sysconfdir" = '${prefix}/etc' && sysconfdir=/etc
 
 # Check for various headers. Alternatives included from compat.h.