I have a jsp where I set a session variable.

```
<% session.setAttribute("user", CrossSession.getUser(token)); %>

```

But when I try to read the session variable "user" within another jsp - which got loaded in an iframe (same host, server, etc.) - then I just get NullPointerException

```
<%= session.getAttribute("user").toString() %>

```

How can I get my session variables in iframes?