Patch from Tony Godshall to use the DISPLAY variable if already set, rather
than always hard-coding it to DISPLAY=:0.
http://bugs.debian.org/705008

Index: tritium/bin/tritium
===================================================================
--- tritium.orig/bin/tritium	2013-04-08 13:18:02.502084580 -0700
+++ tritium/bin/tritium	2013-04-08 13:18:41.986280383 -0700
@@ -149,7 +149,8 @@
         os.execvp( executable, sys.argv[1:] )
 
 if __name__ == '__main__':
-    os.environ[ "DISPLAY" ] = ":0"
+    if not os.environ.has_key("DISPLAY"):
+        os.environ[ "DISPLAY" ] = ":0"
 
     level=logging.INFO
     # right now all we understand is -d for debug
