This is a patch to add mydns support for ddclient. The original patch is written by ta-ta. Thanks!

ddclient-mydns-patch.txt

--- ddclient.orig	2012-07-16 23:32:28.000000000 +0900
+++ /usr/sbin/ddclient	2012-07-20 00:07:06.000000000 +0900
@@ -429,6 +429,11 @@
 	'login'               => setv(T_LOGIN,  0, 0, 0, 'unused',            undef),
 	'client'              => setv(T_STRING, 0, 1, 1, $program,            undef),
     },
+    'mydns-common-defaults'       => {
+        'min-interval'        => setv(T_DELAY,  0, 0, 1, interval('30s'),     0),
+        'max-interval'        => setv(T_DELAY,  0, 0, 1, interval('3d'),     0),
+        'server'              => setv(T_FQDNP,  1, 0, 1, 'www.mydns.jp', undef),
+    },
 );
 my %services = (
     'dyndns1' => {
@@ -563,6 +568,15 @@
 			  $variables{'service-common-defaults'},
 		        ),
     },
+    'mydns' => {
+    'updateable' => undef,
+    'update'     => \&nic_mydns_update,
+    'examples'   => \&nic_mydns_examples,
+    'variables'  => merge(
+			  $variables{'mydns-common-defaults'},
+ 			  $variables{'service-common-defaults'},
+		        ),
+    },
 );
 $variables{'merged'} = merge($variables{'global-defaults'},
 			     $variables{'service-common-defaults'},
@@ -3452,7 +3466,7 @@
 
     ## update each configured host
     foreach my $h (@_) {
-	my $ip = delete $config{$h}{'wantip'};
+        my $ip = delete $config{$h}{'wantip'};
         info("setting IP address to %s for %s", $ip, $h);
         verbose("UPDATE:","updating %s", $h);
 
@@ -3674,5 +3688,74 @@
 ######################################################################
 # vim: ai ts=4 sw=4 tw=78 :
 
-
+######################################################################
+## nic_mydns_examples
+######################################################################
+sub nic_mydns_examples {
+    return <<EoEXAMPLE;
+ 
+o 'mydns'
+ 
+The 'mydns' protocol is used by DNS service offered by www.mydns.jp.
+ 
+Configuration variables applicable to the 'mydns' protocol are:
+  protocol=mydns               ##
+  server=fqdn.of.service       ## defaults to dynamicdns.park-your-domain.com
+  login=service-login          ## login name and password  registered with the service
+  password=service-password    ##
+  fully.qualified.host         ## the host registered with the service.
+ 
+Example ${program}.conf file entries:
+  ## single host update
+  protocol=mydns,                                         \
+  login=my-mydns.jp-login,                               \
+  password=my-mydns.jp-password                          \
+  myhost.mydns.jp
+ 
+EoEXAMPLE
+}
+######################################################################
+## nic_mydns_update
+##
+## Original code by Dan Boardman
+## Modified for MyDNS.jp by ta-ta
+## Modified for latest ddclient by yoneken
+##
+######################################################################
+sub nic_mydns_update {
+ 
+    debug("\nnic_mydns_update -------------------");
+ 
+    ## update each configured host
+    foreach my $h (@_) {
+        my $ip = delete $config{$h}{'wantip'};
+        info("setting IP address to %s for %s", $ip, $h);
+        verbose("UPDATE:","updating %s", $h);
+ 
+        my $url;
+        $url   = "http://$config{$h}{'server'}/login.html";
+ 
+        my $reply = geturl(opt('proxy'), $url, $config{$h}{'login'}, $config{$h}{'password'});
+#        my $reply = geturl(opt('proxy'), $url);
+        if (!defined($reply) || !$reply) {
+            failed("updating %s: Could not connect to %s.", $h, $config{$h}{'server'});
+            last;
+        }
+        last if !header_ok($h, $reply);
+ 
+        my @reply = split /\n/, $reply;
+        if (grep /login_status = 1/i, @reply) {
+            $config{$h}{'ip'}     = $ip;
+            $config{$h}{'mtime'}  = $now;
+            $config{$h}{'status'} = 'good';
+            success("updating %s: good: IP address set to %s", $h, $ip);
+        } else {
+            $config{$h}{'status'} = 'failed';
+            warning("SENT:    %s", $url) unless opt('verbose');
+            warning("REPLIED: %s", $reply);
+            failed("updating %s: Invalid reply.", $h);
+        }
+    }
+}
+ 
+################################################################
 __END__