diff --git a/mozilla/calendar/base/content/calendar-view-core.xml b/mozilla/calendar/base/content/calendar-view-core.xml
index fdf6e7469ca..05830316807 100644
--- a/mozilla/calendar/base/content/calendar-view-core.xml
+++ b/mozilla/calendar/base/content/calendar-view-core.xml
@@ -249,8 +249,8 @@
 
           // Invitation
           if (item.calendar instanceof Components.interfaces.calISchedulingSupport &&
-              item.calendar.isInvitation(item)) { 
-              this.setAttribute("invitation", "true");
+              item.calendar.isInvitation(item)) {
+              this.setAttribute("invitation-status", item.calendar.getInvitedAttendee(item).participationStatus);
           }
         ]]></body>
       </method>
diff --git a/mozilla/calendar/base/themes/pinstripe/calendar-views.css b/mozilla/calendar/base/themes/pinstripe/calendar-views.css
index e5683a8d261..76eac29beb9 100644
--- a/mozilla/calendar/base/themes/pinstripe/calendar-views.css
+++ b/mozilla/calendar/base/themes/pinstripe/calendar-views.css
@@ -574,3 +574,22 @@ description.tooltipBody {
 #calendar-item-context-menu[type="mixed"] .todo-only {
     display: none;
 }
+
+calendar-event-box[invitation-status="NEEDS-ACTION"],
+calendar-editable-item[invitation-status="NEEDS-ACTION"],
+calendar-month-day-box-item[invitation-status="NEEDS-ACTION"] {
+    border: 2px dotted black;
+    opacity: 0.5;
+}
+
+calendar-event-box[invitation-status="TENTATIVE"],
+calendar-editable-item[invitation-status="TENTATIVE"],
+calendar-month-day-box-item[invitation-status="TENTATIVE"] {
+    opacity: 0.5;
+}
+
+calendar-event-box[invitation-status="DECLINED"],
+calendar-editable-item[invitation-status="DECLINED"],
+calendar-month-day-box-item[invitation-status="DECLINED"] {
+    opacity: 0.3;
+}
diff --git a/mozilla/calendar/base/themes/winstripe/calendar-views.css b/mozilla/calendar/base/themes/winstripe/calendar-views.css
index e997430fe48..ed916c18ae4 100644
--- a/mozilla/calendar/base/themes/winstripe/calendar-views.css
+++ b/mozilla/calendar/base/themes/winstripe/calendar-views.css
@@ -575,3 +575,22 @@ description.tooltipBody {
 #calendar-item-context-menu[type="mixed"] .todo-only {
     display: none;
 }
+
+calendar-event-box[invitation-status="NEEDS-ACTION"],
+calendar-editable-item[invitation-status="NEEDS-ACTION"],
+calendar-month-day-box-item[invitation-status="NEEDS-ACTION"] {
+    border: 2px dotted black;
+    opacity: 0.6;
+}
+
+calendar-event-box[invitation-status="TENTATIVE"],
+calendar-editable-item[invitation-status="TENTATIVE"],
+calendar-month-day-box-item[invitation-status="TENTATIVE"] {
+    opacity: 0.6;
+}
+
+calendar-event-box[invitation-status="DECLINED"],
+calendar-editable-item[invitation-status="DECLINED"],
+calendar-month-day-box-item[invitation-status="DECLINED"] {
+    opacity: 0.3;
+}