diff --git a/src/mambatray b/src/mambatray
index 6da0541..9b9ea04 100755
--- a/src/mambatray
+++ b/src/mambatray
@@ -17,6 +17,13 @@ class SystemTrayIcon(QtGui.QSystemTrayIcon):
         QtGui.QSystemTrayIcon.__init__(self, icon, parent)
         menu = QtGui.QMenu(parent)
         
+        # refresh packages cache timer
+        global refreshPackagesTimer, refreshPackagesCacheProcess
+        refreshPackagesTimer = QtCore.QTimer(self)
+        refreshPackagesCacheProcess = QtCore.QProcess(self)
+        self.connect(refreshPackagesTimer, SIGNAL("timeout()"), self.refreshPackagesCache)
+        self.connect(refreshPackagesCacheProcess, SIGNAL("finished(int,QProcess::ExitStatus)"), self.restartRefreshPackagesTimer)
+        
         # software menu
         global softwareManagerProcess, softwareCheckUpgradesProcess, softwareBaseInstallsProcess, dcopServerProcess
         softwareManagerProcess = QtCore.QProcess(self)
@@ -62,7 +69,10 @@ class SystemTrayIcon(QtGui.QSystemTrayIcon):
         self.setContextMenu(menu)
         self.setToolTip(_("openmamba control center"))
         self.activated.connect(self.iconActivated)
-        
+
+        # the first time refresh packages cache after 5 minutes
+        refreshPackagesTimer.start( 5 * 60000 )
+
     def iconActivated(self, reason):
         if reason in (QtGui.QSystemTrayIcon.Trigger, QtGui.QSystemTrayIcon.DoubleClick):
             menu.popup(self.geometry().center())
@@ -77,7 +87,15 @@ class SystemTrayIcon(QtGui.QSystemTrayIcon):
         softwareManagerProcess.execute("/opt/kde/bin/kpackagekit")
 
     def softwareCheckUpgrades(self):
-        softwareCheckUpgradesProcess.execute("/opt/kde/bin/kpackagekit", QtCore.QStringList(list(set(['--updates']))))
+        softwareCheckUpgradesProcess.start("/opt/kde/bin/kpackagekit", ['--updates'])
+
+    def refreshPackagesCache(self):
+        refreshPackagesTimer.stop()
+        refreshPackagesCacheProcess.start("/usr/bin/pkcon", ['refresh'])
+
+    def restartRefreshPackagesTimer(self,status):
+        # check every 4 hours and 31 minutes */
+        refreshPackagesTimer.start( (4 * 60 + 31) * 60000)
 
     def softwareBaseInstalls(self):
         dcopServerProcess.startDetached("/opt/kde3/bin/dcopserver")