class MyPlugin
{
    //constructor for MyPlugin object
    function MyPlugin() {
        register_activation_hook(__FILE__,array(&$this,'activate'));
    }
 
    function activate()
    {
        //initialize some stored plugin stuff
        if (get_option('myplugin_data_1') == '') {
            update_option('myplugin_data_1',array());
        }
        update_option('myplugin_activated',time());
        //etc
     }
}