diff --git a/webtools/bugzilla/Bugzilla/Constants.pm b/webtools/bugzilla/Bugzilla/Constants.pm
index 7411ca0b040..09717486ee6 100644
--- a/webtools/bugzilla/Bugzilla/Constants.pm
+++ b/webtools/bugzilla/Bugzilla/Constants.pm
@@ -78,7 +78,7 @@ use base qw(Exporter);
     
     POS_EVENTS
     EVT_OTHER EVT_ADDED_REMOVED EVT_COMMENT EVT_ATTACHMENT EVT_ATTACHMENT_DATA
-    EVT_PROJ_MANAGEMENT EVT_OPENED_CLOSED EVT_KEYWORD EVT_CC 
+    EVT_PROJ_MANAGEMENT EVT_OPENED_CLOSED EVT_KEYWORD EVT_CC EVT_DEPEND_BLOCK
     
     NEG_EVENTS
     EVT_UNCONFIRMED EVT_CHANGED_BY_ME 
@@ -214,11 +214,12 @@ use constant EVT_PROJ_MANAGEMENT    => 5;
 use constant EVT_OPENED_CLOSED      => 6;
 use constant EVT_KEYWORD            => 7;
 use constant EVT_CC                 => 8;
+use constant EVT_DEPEND_BLOCK       => 9;
 
 use constant POS_EVENTS => EVT_OTHER, EVT_ADDED_REMOVED, EVT_COMMENT, 
                            EVT_ATTACHMENT, EVT_ATTACHMENT_DATA, 
                            EVT_PROJ_MANAGEMENT, EVT_OPENED_CLOSED, EVT_KEYWORD,
-                           EVT_CC;
+                           EVT_CC, EVT_DEPEND_BLOCK;
 
 use constant EVT_UNCONFIRMED        => 50;
 use constant EVT_CHANGED_BY_ME      => 51;
diff --git a/webtools/bugzilla/Bugzilla/User.pm b/webtools/bugzilla/Bugzilla/User.pm
index 6beb16a8b2e..701c1c2b229 100644
--- a/webtools/bugzilla/Bugzilla/User.pm
+++ b/webtools/bugzilla/Bugzilla/User.pm
@@ -1085,7 +1085,9 @@ our %names_to_events = (
     'Target Milestone'       => EVT_PROJ_MANAGEMENT,
     'Attachment description' => EVT_ATTACHMENT_DATA,
     'Attachment mime type'   => EVT_ATTACHMENT_DATA,
-    'Attachment is patch'    => EVT_ATTACHMENT_DATA);
+    'Attachment is patch'    => EVT_ATTACHMENT_DATA,
+    'BugsThisDependsOn'      => EVT_DEPEND_BLOCK,
+    'OtherBugsDependingOnThis' => EVT_DEPEND_BLOCK);
 
 # Returns true if the user wants mail for a given bug change.
 # Note: the "+" signs before the constants suppress bareword quoting.
diff --git a/webtools/bugzilla/checksetup.pl b/webtools/bugzilla/checksetup.pl
index c728c46367c..84c94f10811 100755
--- a/webtools/bugzilla/checksetup.pl
+++ b/webtools/bugzilla/checksetup.pl
@@ -3890,6 +3890,26 @@ if ($dbh->bz_column_info("profiles", "emailflags")) {
     $dbh->bz_drop_column("profiles", "emailflags");    
 }
 
+# Check for any "new" email settings that wouldn't have been ported over
+# during the block above.  Since these settings would have otherwise
+# fallen under EVT_OTHER, we'll just clone those settings.  That way if
+# folks have already disabled all of that mail, there won't be any change.
+{
+    my %events = ("Dependency Tree Changes" => EVT_DEPEND_BLOCK); 
+
+    foreach my $desc (keys %events) {
+        my $event = $events{$desc};
+        $sth = $dbh->prepare("SELECT count(*) FROM email_setting WHERE event = $event");
+        $sth->execute();
+        if (!($sth->fetchrow_arrayref()->[0])) {
+            # No settings in the table yet, so we assume that this is the
+            # first time it's being set.
+            print "Initializing \"$desc\" email_setting ...\n" unless $silent;
+            CloneEmailEvent(EVT_OTHER, $event);
+        }
+    }
+}
+
 sub CloneEmailEvent {
     my ($source, $target) = @_;
 
diff --git a/webtools/bugzilla/template/en/default/account/prefs/email.html.tmpl b/webtools/bugzilla/template/en/default/account/prefs/email.html.tmpl
index 2c75a085c9a..8579992008b 100644
--- a/webtools/bugzilla/template/en/default/account/prefs/email.html.tmpl
+++ b/webtools/bugzilla/template/en/default/account/prefs/email.html.tmpl
@@ -124,6 +124,8 @@ document.write('<input type="button" value="Disable All Mail" onclick="SetCheckb
       description = "The keywords field changes" },
     { id = constants.EVT_CC,
       description = "The CC field changes" },
+    { id = constants.EVT_DEPEND_BLOCK,
+      description = "The dependency tree changes" },
     { id = constants.EVT_OTHER,
       description = "Any field not mentioned above changes" },
 ] %]