applet security connecting to hosts

hello!
An unsigned applet cannot connect to a host other than the originating
host. "connect" in the sense, it cannot use Socket or URLConnection.
But it can open any URL in some other window/frame, using
Appletcontext.showDocument. There is no restriction here, as the
applet is directing the browser to open the URL in an other window,
and the applet itself wont have access to it.

First off, can someone explain the security issue if an unsigned
applet connects to a different host?
Now the subject of this email: With LiveConnect possible, it is easy
to get access to the content of the window that showDocument has
opened. Am I missing something or is this a security issue?

Thanks.