 is cached and when internet access is next
 available the client will inform the server of its subscription. This starts a PushService
 running in the background that will not permanently terminate as long as the user is subscribed
 to some channel, unless the application is uninstalled.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - This is used to access local storage to cache the subscription, so it must currently
          be a viable context.<DD><CODE>channel</CODE> - A string identifie