diff -ur thunar-0.8.0_org/thunar-vfs/thunar-vfs-exec.c thunar-0.8.0/thunar-vfs/thunar-vfs-exec.c
--- thunar-0.8.0_org/thunar-vfs/thunar-vfs-exec.c	2007-01-20 13:39:09.000000000 -0700
+++ thunar-0.8.0/thunar-vfs/thunar-vfs-exec.c	2007-11-14 19:21:56.000000000 -0700
@@ -481,8 +481,21 @@
             }
         }
     }
+#else
+  /* sn_envp needs to be duped in any case for DISPLAY below */
+  sn_envp = g_strdupv(envp);
 #endif
 
+  if (sn_envp != NULL)
+    for (n = 0; sn_envp[n] != NULL; ++n)
+      if ((strlen (sn_envp[n]) > 7) && (g_strncasecmp ("DISPLAY", sn_envp[n], 7) == 0))
+        {
+          gchar *dpyname = gdk_screen_make_display_name(screen);
+          g_free (sn_envp[n]);
+          sn_envp[n] = g_strconcat ("DISPLAY=", dpyname, NULL);
+          g_free (dpyname);
+        }
+
   /* try to spawn the new process */
   succeed = gdk_spawn_on_screen (screen, working_directory, argv, sn_envp, flags, NULL, NULL, &pid, error);