diff --git a/tools/tinderbox/build-seamonkey-util.pl b/tools/tinderbox/build-seamonkey-util.pl
index e6861c9330dc..1a19514cde69 100644
--- a/tools/tinderbox/build-seamonkey-util.pl
+++ b/tools/tinderbox/build-seamonkey-util.pl
@@ -18,7 +18,7 @@ use POSIX qw(sys_wait_h strftime);
 use Cwd;
 use File::Basename; # for basename();
 use Config; # for $Config{sig_name} and $Config{sig_num}
-$::UtilsVersion = '$Revision: 1.37 $ ';
+$::UtilsVersion = '$Revision: 1.38 $ ';
 
 package TinderUtils;
 
@@ -581,6 +581,11 @@ sub BuildIt {
         print_log "current dir is -- " . $ENV{HOST} . ":$build_dir\n";
         print_log "Build Administrator is $Settings::BuildAdministrator\n";
         
+		# Print user comment if there is one.
+		if ($Settings::UserComment) {
+		  print_log "$Settings::UserComment\n";
+		}
+
 		# System id
 		print_log "uname -a = " . `uname -a`;
 
diff --git a/tools/tinderbox/tinder-defaults.pl b/tools/tinderbox/tinder-defaults.pl
index 1e21f5c9cede..7f3a49478675 100644
--- a/tools/tinderbox/tinder-defaults.pl
+++ b/tools/tinderbox/tinder-defaults.pl
@@ -42,6 +42,10 @@ $Tinderbox_server = 'tinderbox-daemon@tinderbox.mozilla.org';
 #- Set if you want to build in a separate object tree
 $ObjDir = '';
 
+# User comment, eg. ip address for dhcp builds.
+# ex: $UserComment = "ip = 208.12.36.108";
+$UserComment = 0;
+
 #-
 #- The rest should not need to be changed
 #-
diff --git a/tools/tinderbox/tinderbox b/tools/tinderbox/tinderbox
index 9e7668a5827b..590bae254752 100755
--- a/tools/tinderbox/tinderbox
+++ b/tools/tinderbox/tinderbox
@@ -26,7 +26,10 @@
 # Assumes that at most two tinderboxes are running
 # simultaneously, depend and clobber.
 #
-# Assumes that if mozconfig exists, use it.
+# Assumes that if mozconfig exists, use it. Format:
+#   mk_add_options MOZ_MAKE_FLAGS=j8
+#   ac_add_options --disable-debug
+#   ac_add_options --enable-optimize
 #