diff --git a/calendar/resources/skin/classic/calendar.css b/calendar/resources/skin/classic/calendar.css
index 604b3a39790..619e7e7f103 100644
--- a/calendar/resources/skin/classic/calendar.css
+++ b/calendar/resources/skin/classic/calendar.css
@@ -1382,7 +1382,7 @@ treechildren::-moz-tree-cell-text(overdue)
 
 treechildren::-moz-tree-row 
 { 
-   border-top             : 1px dotted #AAA; 
+   border-bottom             : 1px dotted #AAA; 
 }
 
 treechildren::-moz-tree-row(overdue,selected)
diff --git a/calendar/resources/skin/modern/calendar.css b/calendar/resources/skin/modern/calendar.css
index 2cb376f7f1b..d799723c64d 100644
--- a/calendar/resources/skin/modern/calendar.css
+++ b/calendar/resources/skin/modern/calendar.css
@@ -1393,7 +1393,7 @@ treechildren::-moz-tree-row(overdue,selected)
 
 treechildren::-moz-tree-row 
 { 
-   border-top             : 1px dotted #AAA; 
+   border-bottom             : 1px dotted #AAA; 
 }
 
 treechildren::-moz-tree-cell-text(duetoday)
diff --git a/calendar/sunbird/themes/winstripe/sunbird/calendar.css b/calendar/sunbird/themes/winstripe/sunbird/calendar.css
index 9da858ed3d4..3e3b09a7cfe 100644
--- a/calendar/sunbird/themes/winstripe/sunbird/calendar.css
+++ b/calendar/sunbird/themes/winstripe/sunbird/calendar.css
@@ -1815,7 +1815,7 @@ treechildren::-moz-tree-row(overdue,selected)
 
 treechildren::-moz-tree-row 
 { 
-   border-top             : 1px dotted #AAA; 
+   border-bottom             : 1px dotted #AAA; 
 }
 
 treechildren::-moz-tree-cell-text(duetoday)