Change the Silent mode by touching the home screen widget 'QuicklySilentMode'.
QuicklySilentMode is the very simple home screen widget, that changes Ringer Mode - Normal, Vibrate, Silent - with one touch.
How to use:
-Long tap at a home screen, and select [Widget] from the menu, and select [QuicklySilentMode] in the widget list.
-Push the QuicklySilentMode button to change the Ringer Mode.
-QuicklySilentMode toggles Normal mode => Vibrate mode => Silent mode, and Normal mode again.