diff -urNb nmap-5.51/nmap.cc nmap-5.51-logoutputfix/nmap.cc
--- nmap-5.51/nmap.cc	2011-02-09 04:37:53.000000000 +0200
+++ nmap-5.51-logoutputfix/nmap.cc	2011-09-13 14:12:45.000000000 +0200
@@ -1287,22 +1287,21 @@
         format_ip_options(o.ipoptions, o.ipoptionslen));
   }
 
-  /* Open the log files, now that we know whether the user wants them appended
-     or overwritten */
+  // Open the log files
   if (normalfilename) {
-    log_open(LOG_NORMAL, o.append_output, normalfilename);
+    log_open(LOG_NORMAL, normalfilename);
     free(normalfilename);
   }
   if (machinefilename) {
-    log_open(LOG_MACHINE, o.append_output, machinefilename);
+    log_open(LOG_MACHINE, machinefilename);
     free(machinefilename);
   }
   if (kiddiefilename) {
-    log_open(LOG_SKID, o.append_output, kiddiefilename);
+    log_open(LOG_SKID, kiddiefilename);
     free(kiddiefilename);
   }
   if (xmlfilename) {
-    log_open(LOG_XML, o.append_output, xmlfilename);
+    log_open(LOG_XML, xmlfilename);
     free(xmlfilename);
   }
 
diff -urNb nmap-5.51/output.cc nmap-5.51-logoutputfix/output.cc
--- nmap-5.51/output.cc	2011-01-21 02:04:16.000000000 +0200
+++ nmap-5.51-logoutputfix/output.cc	2011-09-13 14:13:59.000000000 +0200
@@ -1061,10 +1061,9 @@
   fflush(stderr);
 }
 
-/* Open a log descriptor of the type given to the filename given.  If
-   append is nonzero, the file will be appended instead of clobbered if
-   it already exists.  If the file does not exist, it will be created */
-int log_open(int logt, int append, char *filename) {
+/* Open a log descriptor of the type given to the filename given. If the file
+   does not exist, it will be created. */
+int log_open(int logt, char *filename) {
   int i = 0;
   if (logt <= 0 || logt > LOG_FILE_MASK)
     return -1;
diff -urNb nmap-5.51/output.h nmap-5.51-logoutputfix/output.h
--- nmap-5.51/output.h	2011-01-21 02:04:16.000000000 +0200
+++ nmap-5.51-logoutputfix/output.h	2011-09-13 14:13:17.000000000 +0200
@@ -180,10 +180,9 @@
    corresponding logs immediately */
 void log_flush_all();
 
-/* Open a log descriptor of the type given to the filename given.  If 
-   append is nonzero, the file will be appended instead of clobbered if
-   it already exists.  If the file does not exist, it will be created */
-int log_open(int logt, int append, char *filename);
+/* Open a log descriptor of the type given to the filename given. If the file
+   does not exist, it will be created. */
+int log_open(int logt, char *filename);
 
 /* Output the list of ports scanned to the top of machine parseable
    logs (in a comment, unfortunately).  The items in ports should be