How to put an object into the application scope from a plugin interface

[EL AKARI Mehdi]

Hi,
I'm writing a struts plugin, and i need to put an object into the application scope.
How can i do this.
Note that the plugin interface contains the following methods:
    public void init(ActionServlet servlet, ModuleConfig config) throws 
javax.servlet.ServletException  ;
    public void destroy() ;


thanks 
Mehdi