diff --git a/ChangeLog.md b/ChangeLog.md
index 19633f3..f703f3a 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -34,6 +34,13 @@ repository history](https://github.com/ddclient/ddclient/commits/master).
   * Deprecated built-in web IP discovery services are not listed in the output
     of `--list-web-services`.
     [#682](https://github.com/ddclient/ddclient/pull/682)
+  * `dyndns2`: Support for "wait" response lines has been removed.  The Dyn
+    documentation does not mention such responses, and the code to handle them,
+    untouched since at least 2006, is believed to be obsolete.
+    [#709](https://github.com/ddclient/ddclient/pull/709)
+  * `dyndns2`: The obsolete `static` and `custom` options have been removed.
+    Setting the options may produce a warning.
+    [#709](https://github.com/ddclient/ddclient/pull/709)
 
 ### New features
 
diff --git a/ddclient.conf.in b/ddclient.conf.in
index 8a336ac..1c7ae35 100644
--- a/ddclient.conf.in
+++ b/ddclient.conf.in
@@ -81,26 +81,6 @@ pid=@runstatedir@/ddclient.pid		# record PID in file.
 # protocol=dyndns2			\
 # your-dynamic-host.dyndns.org
 
-##
-## dyndns.org static addresses
-##
-## (supports variables: wildcard,mx,backupmx)
-##
-# static=yes,				\
-# server=members.dyndns.org,		\
-# protocol=dyndns2			\
-# your-static-host.dyndns.org
-
-##
-## dyndns.org custom addresses
-##
-## (supports variables: wildcard,mx,backupmx)
-##
-# custom=yes,				\
-# server=members.dyndns.org,		\
-# protocol=dyndns2			\
-# your-domain.top-level,your-other-domain.top-level
-
 ##
 ## ZoneEdit (zoneedit.com)
 ##
diff --git a/ddclient.in b/ddclient.in
index c13e355..332f086 100755
--- a/ddclient.in
+++ b/ddclient.in
@@ -709,7 +709,6 @@ our %variables = (
     'dyndns-common-defaults' => {
         'backupmx'            => setv(T_BOOL,  0, 1, 0,                    undef),
         'mx'                  => setv(T_OFQDN, 0, 1, undef,                undef),
-        'static'              => setv(T_BOOL,  0, 1, 0,                    undef),
         'wildcard'            => setv(T_BOOL,  0, 1, 0,                    undef),
     },
 );
@@ -848,6 +847,7 @@ our %protocols = (
         'variables' => {
             %{$variables{'protocol-common-defaults'}},
             %{$variables{'dyndns-common-defaults'}},
+            'static' => setv(T_BOOL, 0, 1, 0, undef),
         },
     },
     'dyndns2' => {
@@ -857,7 +857,6 @@ our %protocols = (
         'variables' => {
             %{$variables{'protocol-common-defaults'}},
             %{$variables{'dyndns-common-defaults'}},
-            'custom' => setv(T_BOOL,   0, 1, 0,             undef),
             'script' => setv(T_STRING, 0, 1, '/nic/update', undef),
         },
     },
@@ -4015,8 +4014,6 @@ Configuration variables applicable to the 'dyndns2' protocol are:
   server=fqdn.of.service       ## defaults to members.dyndns.org
   script=/path/to/script       ## defaults to /nic/update
   backupmx=no|yes              ## indicates that this host is the primary MX for the domain.
-  static=no|yes                ## indicates that this host has a static IP address.
-  custom=no|yes                ## indicates that this host is a 'custom' top-level domain name.
   mx=any.host.domain           ## a host MX'ing for this host definition.
   wildcard=no|yes              ## add a DNS wildcard CNAME record that points to <host>
   login=service-login          ## login name and password  registered with the service
@@ -4050,7 +4047,6 @@ EoEXAMPLE
 ######################################################################
 sub nic_dyndns2_update {
     debug("\nnic_dyndns2_update -------------------");
-    my @groups = group_hosts_by(\@_, qw(login password server script static custom wildcard mx backupmx wantipv4 wantipv6));
     my %errors = (
        'badauth' => 'Bad authorization (username or password)',
        'badsys' => 'The system parameter given was not valid',
@@ -4064,7 +4060,18 @@ sub nic_dyndns2_update {
        'dnserr' => 'System error: DNS error encountered. Contact support@dyndns.org',
        'nochg' => 'No update required; unnecessary attempts to change to the current address are considered abusive',
     );
-    for my $group (@groups) {
+    my @group_by_attrs = qw(
+        backupmx
+        login
+        mx
+        password
+        script
+        server
+        wantipv4
+        wantipv6
+        wildcard
+    );
+    for my $group (group_hosts_by(\@_, @group_by_attrs)) {
         my @hosts = @{$group->{hosts}};
         my %groupcfg = %{$group->{cfg}};
         my $hosts = join(',', @hosts);
@@ -4072,21 +4079,9 @@ sub nic_dyndns2_update {
         my $ipv6 = $groupcfg{'wantipv6'};
         delete $config{$_}{'wantipv4'} for @hosts;
         delete $config{$_}{'wantipv6'} for @hosts;
-        info("setting IPv4 address to %s for %s", $ipv4, $hosts) if $ipv4;
-        info("setting IPv6 address to %s for %s", $ipv6, $hosts) if $ipv6;
-        verbose("UPDATE:", "updating %s", $hosts);
-        my $url = "$groupcfg{'server'}$groupcfg{'script'}?system=";
-        if ($groupcfg{'custom'}) {
-            warning("updating %s: 'custom' and 'static' may not be used together. ('static' ignored)", $hosts)
-                if $groupcfg{'static'};
-            $url .= 'custom';
-        } elsif ($groupcfg{'static'}) {
-            $url .= 'statdns';
-        } else {
-            $url .= 'dyndns';
-        }
-        $url .= "&hostname=$hosts";
-        $url .= "&myip=";
+        info("$hosts: setting IPv4 address to $ipv4") if $ipv4;
+        info("$hosts: setting IPv6 address to $ipv6") if $ipv6;
+        my $url = "$groupcfg{'server'}$groupcfg{'script'}?hostname=$hosts&myip=";
         $url .= $ipv4 if $ipv4;
         if ($ipv6) {
             $url .= "," if $ipv4;
@@ -4105,65 +4100,64 @@ sub nic_dyndns2_update {
             password => $groupcfg{'password'},
         ) // '';
         if ($reply eq '') {
-            failed("updating %s: Could not connect to %s.", $hosts, $groupcfg{'server'});
+            failed("$hosts: Could not connect to $groupcfg{'server'}");
             next;
         }
         next if !header_ok($hosts, $reply);
-        my @reply = split /\n/, $reply;
-        my $state = 'header';
-        for my $line (@reply) {
-            if ($state eq 'header') {
-                $state = 'body';
-            } elsif ($state eq 'body') {
-                $state = 'results' if $line eq '';
-            } elsif ($state =~ /^results/) {
-                $state = 'results2';
-                # bug #10: some dyndns providers does not return the IP so
-                # we can't use the returned IP
-                my ($status, $returnedips) = split / /, lc $line;
-                for my $h (@hosts) {
-                    $config{$h}{'status-ipv4'} = $status if $ipv4;
-                    $config{$h}{'status-ipv6'} = $status if $ipv6;
-                }
-                if ($status eq 'good') {
-                    for my $h (@hosts) {
-                        $config{$h}{'ipv4'} = $ipv4 if $ipv4;
-                        $config{$h}{'ipv6'} = $ipv6 if $ipv6;
-                        $config{$h}{'mtime'} = $now;
-                    }
-                    success("updating %s: %s: IPv4 address set to %s", $hosts, $status, $ipv4) if $ipv4;
-                    success("updating %s: %s: IPv6 address set to %s", $hosts, $status, $ipv6) if $ipv6;
-                } elsif (exists $errors{$status}) {
-                    if ($status eq 'nochg') {
-                        warning("updating %s: %s: %s", $hosts, $status, $errors{$status});
-                        for my $h (@hosts) {
-                            $config{$h}{'ipv4'} = $ipv4 if $ipv4;
-                            $config{$h}{'ipv6'} = $ipv6 if $ipv6;
-                            $config{$h}{'mtime'} = $now;
-                            $config{$h}{'status-ipv4'} = 'good' if $ipv4;
-                            $config{$h}{'status-ipv6'} = 'good' if $ipv6;
-                        }
-                    } else {
-                        failed("updating %s: %s: %s", $hosts, $status, $errors{$status});
-                    }
-                } elsif ($status =~ /w(\d+)(.)/) {
-                    my ($wait, $units) = ($1, lc $2);
-                    my ($sec, $scale) = ($wait, 1);
-                    ($scale, $units) = (1, 'seconds') if $units eq 's';
-                    ($scale, $units) = (60, 'minutes') if $units eq 'm';
-                    ($scale, $units) = (60*60, 'hours') if $units eq 'h';
-                    $sec = $wait * $scale;
-                    for my $h (@hosts) {
-                        $config{$h}{'wtime'} = $now + $sec;
-                    }
-                    warning("updating %s: %s: wait %s %s before further updates", $hosts, $status, $wait, $units);
-                } else {
-                    failed("updating %s: unexpected status (%s)", $hosts, $line);
-                }
-            }
+        # Some services can return 200 OK even if there is an error (e.g., bad authentication,
+        # updates too frequent) so the body of the response must also be checked.
+        (my $body = $reply) =~ s/^.*?\n\n//s;
+        my @reply = split(qr/\n/, $body);
+        if (!@reply) {
+            failed("$hosts: Could not connect to $groupcfg{'server'}");
+            next;
+        }
+        # From <https://help.dyn.com/remote-access-api/return-codes/>:
+        #
+        #   If updating multiple hostnames, hostname-specific return codes are given one per line,
+        #   in the same order as the hostnames were specified.  Return codes indicating a failure
+        #   with the account or the system are given only once.
+        #
+        # TODO: There is no mention of what happens if multiple IP addresses are supplied (e.g.,
+        # IPv4 and IPv6) for a host.  If one address fails to update and the other doesn't, is that
+        # one error status line?  An error status line and a success status line?  Or is an update
+        # considered to be all-or-nothing and the status applies to the operation as a whole?  If
+        # the IPv4 address changes but not the IPv6 address does that result in a status of "good"
+        # because the set of addresses for a host changed even if a subset did not?
+        #
+        # TODO: The logic below applies the last line's status to all hosts.  Change it to apply
+        # each status to its corresponding host.
+        for my $line (@reply) {
+            # The IP address normally comes after the status, but we ignore it.  We could compare
+            # it with the expected address and mark the update as failed if it differs, but (1)
+            # some services do not return the IP; and (2) comparison is brittle (e.g.,
+            # 192.000.002.001 vs. 192.0.2.1) and false errors could cause high load on the service
+            # (an update attempt every min-error-interval instead of every max-interval).
+            (my $status = $line) =~ s/ .*$//;
+            if ($status eq 'nochg') {
+                warning("$hosts: $status: $errors{$status}");
+                $status = 'good';
+            }
+            for my $h (@hosts) {
+                $config{$h}{'status-ipv4'} = $status if $ipv4;
+                $config{$h}{'status-ipv6'} = $status if $ipv6;
+            }
+            if ($status ne 'good') {
+                if (exists($errors{$status})) {
+                    failed("$hosts: $status: $errors{$status}");
+                } else {
+                    failed("$hosts: unexpected status: $line");
+                }
+                next;
+            }
+            for my $h (@hosts) {
+                $config{$h}{'ipv4'} = $ipv4 if $ipv4;
+                $config{$h}{'ipv6'} = $ipv6 if $ipv6;
+                $config{$h}{'mtime'} = $now;
+            }
+            success("$hosts: IPv4 address set to $ipv4") if $ipv4;
+            success("$hosts: IPv6 address set to $ipv6") if $ipv6;
         }
-        failed("updating %s: Could not connect to %s.", $hosts, $groupcfg{'server'})
-            if $state ne 'results2';
     }
 }