diff --git a/CHANGELOG b/CHANGELOG
index d9e752806..09183e775 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,4 +1,12 @@
 # Nmap Changelog ($Id$); -*-text-*-
+
+o Nmap's output options (-oA, -oX, etc.) now support strftime()-like
+  conversions in the filename.  %H, %M, %S, %T, %R, %m, %d, %y, and
+  %Y are all the same as in strftime().  %t is the same as %H%M%S,
+  %r is the same as %H%M, and %D is the same as %m%d%y.  This means
+  that "-oX 'scan-%T-%D.xml'" uses an XML file in the form of
+  "scan-14:48:40-121307.xml". [Kris]
+
 4.50
 
 o Bumped up the version number to the big 4.50!
diff --git a/docs/refguide.xml b/docs/refguide.xml
index ea9d0e5d7..e73787c68 100644
--- a/docs/refguide.xml
+++ b/docs/refguide.xml
@@ -2868,6 +2868,18 @@ compatibility feature of Nmap will cause the creation of
 <filename>G-</filename> and <filename>Xscan.xml</filename>
 respectively.</para>
 
+<para>All of these arguments support <function>strftime()</function>-like
+conversions in the filename.  <literal>%H</literal>, <literal>%M</literal>,
+<literal>%S</literal>, <literal>%T</literal>, <literal>%R</literal>,
+<literal>%m</literal>, <literal>%d</literal>, <literal>%y</literal>,
+and <literal>%Y</literal> are all exactly the same as in
+<function>strftime()</function>.  <literal>%t</literal> is the same as
+<literal>%H%M%S</literal>, <literal>%r</literal> is the same as
+<literal>%H%M</literal>, and <literal>%D</literal> is the same as
+<literal>%m%d%y</literal>.  So <option>-oX 'scan-%T-%D.xml'</option>
+will use an XML file in the form of
+<filename>scan-14:48:40-121307.xml</filename>.</para>
+
 <para>Nmap also offers options to control scan verbosity and to append
 to output files rather than clobbering them.  All of these options are
 described below.</para>
diff --git a/nmap.cc b/nmap.cc
index 081c2aa71..4a403dc63 100644
--- a/nmap.cc
+++ b/nmap.cc
@@ -472,6 +472,8 @@ int nmap_main(int argc, char *argv[]) {
   int num_host_exp_groups;
   char *machinefilename = NULL, *kiddiefilename = NULL, 
     *normalfilename = NULL, *xmlfilename = NULL;
+  time_t now;
+  struct tm *tm;
   HostGroupState *hstate = NULL;
   char *endptr = NULL;
   struct scan_lists *ports = NULL;
@@ -647,6 +649,9 @@ int nmap_main(int argc, char *argv[]) {
   win_pre_init();
 #endif
 
+  now = time(NULL);
+  tm = localtime(&now);
+
   /* OK, lets parse these args! */
   optind = 1; /* so it can be called multiple times */
   while((arg = getopt_long_only(argc,fakeargv,"6Ab:D:d::e:Ffg:hIi:M:m:nO::o:P:p:qRrS:s:T:Vv", long_options, &option_index)) != EOF) {
@@ -816,23 +821,23 @@ int nmap_main(int argc, char *argv[]) {
       } else if (strcmp(long_options[option_index].name, "webxml") == 0) {
 	o.setXSLStyleSheet("http://www.insecure.org/nmap/data/nmap.xsl");
       } else if (strcmp(long_options[option_index].name, "oN") == 0) {
-	normalfilename = optarg;
+	normalfilename = logfilename(optarg, tm);
       } else if (strcmp(long_options[option_index].name, "oG") == 0 ||
 		 strcmp(long_options[option_index].name, "oM") == 0) {
-	machinefilename = optarg;
+	machinefilename = logfilename(optarg, tm);
       } else if (strcmp(long_options[option_index].name, "oS") == 0) {
-	kiddiefilename = optarg;
+	kiddiefilename = logfilename(optarg, tm);
       } else if (strcmp(long_options[option_index].name, "oH") == 0) {
 	fatal("HTML output is not directly supported, though Nmap includes an XSL for transforming XML output into HTML.  See the man page.");
       } else if (strcmp(long_options[option_index].name, "oX") == 0) {
-	xmlfilename = optarg;
+	xmlfilename = logfilename(optarg, tm);
       } else if (strcmp(long_options[option_index].name, "oA") == 0) {
 	char buf[MAXPATHLEN];
-	Snprintf(buf, sizeof(buf), "%s.nmap", optarg);
+	Snprintf(buf, sizeof(buf), "%s.nmap", logfilename(optarg, tm));
 	normalfilename = strdup(buf);
-	Snprintf(buf, sizeof(buf), "%s.gnmap", optarg);
+	Snprintf(buf, sizeof(buf), "%s.gnmap", logfilename(optarg, tm));
 	machinefilename = strdup(buf);
-	Snprintf(buf, sizeof(buf), "%s.xml", optarg);
+	Snprintf(buf, sizeof(buf), "%s.xml", logfilename(optarg, tm));
 	xmlfilename = strdup(buf);
       } else if (strcmp(long_options[option_index].name, "thc") == 0) {
 	printf("!!Greets to Van Hauser, Plasmoid, Skyper and the rest of THC!!\n");
@@ -1008,7 +1013,7 @@ int nmap_main(int argc, char *argv[]) {
         fatal("Unknown argument to -O.");
       break;
     case 'o':
-      normalfilename = optarg;
+      normalfilename = logfilename(optarg, tm);
       break;
     case 'P': 
       if (*optarg == '\0' || *optarg == 'I' || *optarg == 'E')
@@ -1244,10 +1249,6 @@ int nmap_main(int argc, char *argv[]) {
 
   if (!o.interactivemode) {
     char tbuf[128];
-    struct tm *tm;
-    time_t now = time(NULL);
-    if (!(tm = localtime(&now))) 
-      fatal("Unable to get current localtime()#!#");
     // ISO 8601 date/time -- http://www.cl.cam.ac.uk/~mgk25/iso-time.html 
     if (strftime(tbuf, sizeof(tbuf), "%Y-%m-%d %H:%M %Z", tm) <= 0)
       fatal("Unable to properly format time");
diff --git a/output.cc b/output.cc
index 1696cfa1b..6221edaff 100644
--- a/output.cc
+++ b/output.cc
@@ -830,6 +830,77 @@ char* xml_convert (const char* str) {
   return temp;
 }
 
+char *logfilename(const char *str, struct tm *tm)
+{
+	char *ret, *end, *p;
+	char tbuf[10];
+	int retlen = strlen(str) * 6 + 1;
+
+	ret = (char *) safe_malloc(retlen);
+	end = ret + retlen;
+
+	for (p = ret; *str; str++) {
+		if (*str == '%') {
+			str++;
+
+			if (!*str)
+				break;
+
+			switch (*str) {
+			case 'H':
+				strftime(tbuf, sizeof tbuf, "%H", tm);
+				break;
+			case 'M':
+				strftime(tbuf, sizeof tbuf, "%M", tm);
+				break;
+			case 'S':
+				strftime(tbuf, sizeof tbuf, "%S", tm);
+				break;
+			case 'T':
+				strftime(tbuf, sizeof tbuf, "%T", tm);
+				break;
+			case 't':
+				strftime(tbuf, sizeof tbuf, "%H%M%S", tm);
+				break;
+			case 'R':
+				strftime(tbuf, sizeof tbuf, "%R", tm);
+				break;
+			case 'r':
+				strftime(tbuf, sizeof tbuf, "%H%M", tm);
+				break;
+			case 'm':
+				strftime(tbuf, sizeof tbuf, "%m", tm);
+				break;
+			case 'd': 
+				strftime(tbuf, sizeof tbuf, "%d", tm);
+				break;
+			case 'y': 
+				strftime(tbuf, sizeof tbuf, "%y", tm);
+				break;
+			case 'Y': 
+				strftime(tbuf, sizeof tbuf, "%Y", tm);
+				break;
+			case 'D': 
+				strftime(tbuf, sizeof tbuf, "%m%d%y", tm);
+				break;
+			default:
+				*p++ = *str;
+				continue;
+			}
+
+			assert(end - p > 1);
+			Strncpy(p, tbuf, end - p - 1);
+			p += strlen(tbuf);
+		} else {
+			*p++ = *str;
+		}
+	}
+
+	*p = 0;
+
+	return (char *) safe_realloc(ret, strlen(ret) + 1);
+}
+
 /* This is the workhorse of the logging functions.  Usually it is
    called through log_write(), but it can be called directly if you
    are dealing with a vfprintf-style va_list.  Unlike log_write, YOU
diff --git a/output.h b/output.h
index 772bbda44..6ec6654ad 100644
--- a/output.h
+++ b/output.h
@@ -138,6 +138,8 @@ void printportoutput(Target *currenths, PortList *plist);
    in a certain place to conform to DTD. */
 void printmacinfo(Target *currenths);
 
+char *logfilename(const char *str, struct tm *tm);
+
 /* Write some information (printf style args) to the given log stream(s).
    Remember to watch out for format string bugs. */
 void log_write(int logt, const char *fmt, ...)