diff --git a/mozilla/calendar/resources/content/weekView.js b/mozilla/calendar/resources/content/weekView.js
index 62194813651..e239a5056fd 100644
--- a/mozilla/calendar/resources/content/weekView.js
+++ b/mozilla/calendar/resources/content/weekView.js
@@ -473,11 +473,11 @@ WeekView.prototype.refreshDisplay = function( )
       document.getElementById( "week-header-date-text-"+dayIndex ).setAttribute( "value", NewArrayOfDayNames[col] );
          
       if( isOnlyWorkDays && isDayOff[(Offset + col) % 7]) {
-         document.getElementById( "weekview-column-day-"+dayIndex ).setAttribute( "collapsed", "true" );
-         document.getElementById( "weekview-header-column-day-"+dayIndex ).setAttribute( "collapsed", "true" );
+         document.getElementById( "weekview-column-day-"+dayIndex ).setAttribute( "hidden", "true" );
+         document.getElementById( "weekview-header-column-day-"+dayIndex ).setAttribute( "hidden", "true" );
       } else {
-         document.getElementById( "weekview-column-day-"+dayIndex ).removeAttribute( "collapsed" );
-         document.getElementById( "weekview-header-column-day-"+dayIndex ).removeAttribute( "collapsed" );
+         document.getElementById( "weekview-column-day-"+dayIndex ).removeAttribute( "hidden" );
+         document.getElementById( "weekview-header-column-day-"+dayIndex ).removeAttribute( "hidden" );
       }
          
       // advance to next day